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it doesn't Help (on mine when i replaced the pump) the return line in the tank is directly pointed at the Sock. So i added a 4" hose to let the fuel get by the sock..... I have not heard the noise once since........................... it was 97* here in NC today, and I'm happy to say..... Its fixed.
This is a problem I posted about (perhaps earlier in this thread) some time ago and did a number of things to try and resolve it. My set up is quite different than most of you as I am turbocharged. My under-hood temps are quite high, but low enough that only one strut tower plastic cap is melting AND my AC still works fine. :-)
I first noticed this problem at the drag strip in summer months, with the stock engine, stock regulator, boost over 12 psi and a Walbro 255 in tank pump. It would only happen after multiple passes and ALWAYS cleared up within 15 minutes of leaving the dragstrip and hitting the open road at 55 mph.
After building the new engine in July 2011, I really started seeing the problem. More HP = more heat. Running the AC for 30-45 mins which put the coolant around 205-210 in 95 degree weather sets it off every time. And of course the good old drag strip heat soak. I tried a variety of fixes such as E0 fuel, replaced the Walbro with another, built a deflector to keep returned fuel from shooting straight into the sock and direct wiring the pump via relay directly to the rear mount battery. Finally I installed an Aeromotive Stealth 340 in-tank pump. The problem seemed gone. But the cooler weather is what really fixed it. That and the issue drove me crazy so I bought a boat to distract me. That and a divorce got me through summer 2012 without really noticing the issue.
Now we are entering summer 2013 and the problem is most certainly still here. My current setup is as follows:
Aeromotive Stealth 340
Stock regulator
main fuel feed through the cold start injector fitting
fuel lines wrapped in area near exhaust manifold (not on frame side)
17 psi of boost
I have been experimenting with fuel temp lately and have discovered the fuel lines to be around 135 degrees when the lean issues occur. I measured the outside of the fuel tank at 125 degrees and the fuel filler opening at 105. The issue occurred last week under the following conditions:
Coolant temp 208 degrees, car very heat soaked from 1.5 hr drive on highway/interstate. Boost below 13 psi perfect fueling, boost 13 and higher severe lean condition.
I installed an Aeromotive A1000 external regulator so the fuel would return before entering the fuel rails. A one hour drive with AC on brought the fuel lines and regulator to 135 degrees. The filler opening measured 111. The Aeromotive regulator went nuts and dropped fuel pressure severely. I adjusted it 1.25 turns in to get the AFR back where it should have been. After filling the tank with cold fuel, I ended up adjusting it back where it started before the heat issues that day. I let the car cool for 1 hr and the regulator became ambient temp. We cycled the pump several times and the regulator became very hot once again, verifying the fuel in the tank was hot.
Conclusion:
The heat is entering the fuel via some method other than the fuel rails. If anything, the fuel was even hotter with the rails dead-headed.
The heat is coming from one or more of the following:
1> The exposed metal lines in the engine bay
2> The exposed metal lines along the frame rail alongside the manifold and the transmission
3> The tank itself, either via the muffler and/or engine bay heat flowing to rear of car
Very frustrated to be back at square zero again. 17 psi and 17:1 AFR equals violent detonation.
This is a problem I posted about (perhaps earlier in this thread) some time ago and did a number of things to try and resolve it. My set up is quite different than most of you as I am turbocharged. My under-hood temps are quite high, but low enough that only one strut tower plastic cap is melting AND my AC still works fine. :-)
I first noticed this problem at the drag strip in summer months, with the stock engine, stock regulator, boost over 12 psi and a Walbro 255 in tank pump. It would only happen after multiple passes and ALWAYS cleared up within 15 minutes of leaving the dragstrip and hitting the open road at 55 mph.
After building the new engine in July 2011, I really started seeing the problem. More HP = more heat. Running the AC for 30-45 mins which put the coolant around 205-210 in 95 degree weather sets it off every time. And of course the good old drag strip heat soak. I tried a variety of fixes such as E0 fuel, replaced the Walbro with another, built a deflector to keep returned fuel from shooting straight into the sock and direct wiring the pump via relay directly to the rear mount battery. Finally I installed an Aeromotive Stealth 340 in-tank pump. The problem seemed gone. But the cooler weather is what really fixed it. That and the issue drove me crazy so I bought a boat to distract me. That and a divorce got me through summer 2012 without really noticing the issue.
Now we are entering summer 2013 and the problem is most certainly still here. My current setup is as follows:
Aeromotive Stealth 340
Stock regulator
main fuel feed through the cold start injector fitting
fuel lines wrapped in area near exhaust manifold (not on frame side)
17 psi of boost
I have been experimenting with fuel temp lately and have discovered the fuel lines to be around 135 degrees when the lean issues occur. I measured the outside of the fuel tank at 125 degrees and the fuel filler opening at 105. The issue occurred last week under the following conditions:
Coolant temp 208 degrees, car very heat soaked from 1.5 hr drive on highway/interstate. Boost below 13 psi perfect fueling, boost 13 and higher severe lean condition.
I installed an Aeromotive A1000 external regulator so the fuel would return before entering the fuel rails. A one hour drive with AC on brought the fuel lines and regulator to 135 degrees. The filler opening measured 111. The Aeromotive regulator went nuts and dropped fuel pressure severely. I adjusted it 1.25 turns in to get the AFR back where it should have been. After filling the tank with cold fuel, I ended up adjusting it back where it started before the heat issues that day. I let the car cool for 1 hr and the regulator became ambient temp. We cycled the pump several times and the regulator became very hot once again, verifying the fuel in the tank was hot.
Conclusion:
The heat is entering the fuel via some method other than the fuel rails. If anything, the fuel was even hotter with the rails dead-headed.
The heat is coming from one or more of the following:
1> The exposed metal lines in the engine bay
2> The exposed metal lines along the frame rail alongside the manifold and the transmission
3> The tank itself, either via the muffler and/or engine bay heat flowing to rear of car
Very frustrated to be back at square zero again. 17 psi and 17:1 AFR equals violent detonation.
Aeromotive
FINALLY!!! I mentioned over a year ago that someone should try to modify a return line before the returned fuel reaches the engine bay so that the returning fuel won't soak any heat. But you just verified that the heat is still generated. Question for you. Do you have a fuel tank heat shield in place?
Yes all stock shields in place. Muffler is a straight through Magnaflow, except it does have an outlet on the inlet side as well. But the point is there isn't much in there to trap/catch heat as mufflers go. I'm planning to buy one of those remote outdoor thermometers tomorrow. I'm going to attach the sensor to a magnet and try to document ambient temps between the tank and heatshield and along the transmission tunnel where the fuel line runs.
I didn't mention in the previous post, but after the trip I measured my brake master cylinder at 145 degrees. It's about the same distance from the manifold as the fuel lines so it is safe to say the lines are getting some heat. I wonder how much heat a non-turbo third gen is seeing in these spots. I know just the car to test!
Yes all stock shields in place. Muffler is a straight through Magnaflow, except it does have an outlet on the inlet side as well. But the point is there isn't much in there to trap/catch heat as mufflers go. I'm planning to buy one of those remote outdoor thermometers tomorrow. I'm going to attach the sensor to a magnet and try to document ambient temps between the tank and heatshield and along the transmission tunnel where the fuel line runs.
I didn't mention in the previous post, but after the trip I measured my brake master cylinder at 145 degrees. It's about the same distance from the manifold as the fuel lines so it is safe to say the lines are getting some heat. I wonder how much heat a non-turbo third gen is seeing in these spots. I know just the car to test!
I'm just wondering, how is your fuel pump wired? stock wiring or a hot wire kit? underdrive pulleys?
This post is long. Basic info provided prior to the dotted line. Details follow.
1. I am gonna move the regulator off the motor, sending the return fuel home before it gets too hot.
2. I will tell the results after it's done.
3. My results may be more meaningful to most people than the guy above who has a turbo, because my car is stock and turbocharged cars are known to overheat everything under hood. Also, my car is brand new and totally stock.
I am new to this thread. I have the dreaded fuel boiling plague. Years ago, I had 15 of these cars, and never had trouble like this with them. (I had put 260k miles on one of them, and 600k on the others, collectively)
Now, after spending 10 years without a third gen daily driver, I find my dream car (for daily use, in the third gen catagory), an 87 gta hardtop, with less than 3k original miles on it.
350 auto, all stock. A new car.
Car is trouble free, except when it is over 80° outside AND I drive in city streets; the gas boils something awful. I was getting the loud high pitched sound from the pump, the stink of gasoline vapors, the sound of the gas boiling, and eventual sputtering and dying of the car. This happened 3 times prior to the original pump burning out.
Now, I've replaced that pump. I did everything I could after reading most of this thread. Used the best parts from ACDELCO:
Replaced
1. fuel sock
2. metal fuel filter
3. rubber hoses
4. delco pump, made in Brazil
5. Fuel pump relay
Then,
6. blew out lines in sender likewise
7. blew out fuel lines in car with high pressure air, in reverse direction
8. checked over run valve
9. checked charcoal canister system
10. Would've replaced sender unit, but it came a day too late. ($300 part)
Everything looked new inside and out.
This being a new, untouched car proves that even a totally stock car with no miles on it, will have the problem. The problem is not the result of people's "improvements" or tampering of any kind.
Now, with that work done, the car doesn't sputter and die anymore, the pump doesn't whine anymore, but the fuel boils like crazy. It's so loud you can hear it boiling without taking the cap off. When you do take the cap off, you are overcome with fumes, you can't breathe anywhere near the filler area, and it continues boiling even after the car is shut off. It stinks, and it wastes fuel. I know that if you boil a kettle of water, pretty soon it's all gone. How long would it would take to boil the whole tank of gas. 1 hour? More?
AND, outside temp has not exceeded 85°, and the trouble happens even at 80°.
Mind you, except for this particular car which is in northeast USA, all of my experience with these cars was in Florida, where it was routinely in the 100°'s and high humidity, and I always had a/c on, and always relied on the cars for city use for business, and daily would sit around with a/c on, in parking lots, etc, for my business. Those cars had no hint of trouble in those temps, under those conditions. Now, I can't take a 20 minute drive on a 80 degree day without boiling gas. If i had this car with this problem in Florida under those conditions, it probably wouldn't last 5 minutes.
I have not tried taking off the gas cap yet, to see if that would help.
The only other thing of note is that the previous fuel pump never was very good. I didn't realize this until after the pump was replaced. Besides the above symptoms, the old pump always made the car take 6 to 8 seconds on startup in mornings, whereas the new pump stars the car from cold in 1 second. The old pump was louder in general, even when cold. The new pump is almost inaudible. Also, the car runs with only 1 of the 2 cooling fans functioning. I intend to hot wire the #2 fan.
My next move is gonna be to put a fuel pressure regulator away from the motor, and run the return fuel from the regulator to the tank. I will first try putting the regulator near the battery, and I will use heat shield to keep the engine heat away. I may be able to put a ram air setup, just for the fuel regulator. There should be some way to pipe air up there. If this does not work I will move regulator under car at position of fuel filter, back near the tank. I finally figured out which fittings were needed to convert the factory hard lines to aeroquip fittings, so I can hook up the aftermarket regulator, which will be Aeromotive (USA). If anyone wants the list of crap you need to do this, I can provide it. It is $350, but I'd advise waiting till I do this to see if it will work. (I can't imagine this could fail with the regulator back next to the tank. I believe the reason the car companies went to returnless fuel systems is because of this problem, and because boiling the fuel serves no practical purpose whatsoever.)
When I had my sender out of the tank, I wanted to fix the return so it didn't shoot into the sock, but there was not enough pipe there to work with, and I didnt have time to mess with it. But that should be a moot point after the regulator is moved upstream.
To save time, about the regulator, I will leave the factory regulator in there, and put a plug on the outlet of the fuel rail. So, the factory regulator won't do anything at all, and no fuel will leave the rails. It will be essentially returnless, as far as the engine knows. (as long as it does not look at the regulator).
My secondary fan never comes on. (my car does not get to 238 degrees, so I guess that is why it does not come on.) But I am gonna fix it so it is on all the time. Since I always use a/c, that will make sure the primary fan is always on too. So I'll have both fans. That may help the fuel boiling somewhat, but I'm not gonna bet on it.
This last bit is off topic. it's about air conditioning...
My main motivation for fixing the second fan is that my a/c condensor is only using 1/2 of it's efficiency with the single fan, and that only nets a 60 degree outlet temp at the vents, at idle, standing still, which is unacceptable. The a/c goes down to 40 degrees at 60mph. I just installed a regulator into the hot side, to get effective cooling at idle, but I will need the full use of the condensor for that regulator to function. If anyone else is unhappy with slow speed and idle a/c performance, I can point you towards the regulator, which installs in place of the orifice tube, and costs only $10. Even without the second fan, I have already improved my a/c by 10 degrees at idle. This unit sort of makes up for the shortcomings of the ccot system, and was in fact invented my the engineer who came up with the ccot system in the first place. (the ccot system lowered the cost per car $200, and made us all have crappy a/c whenever we weren't moving fast... in the old days, prior to 1977, there were proper regulators to compensate for this, and a/c was 37 degrees at the vent at all times, even a dead stop at idle. Plus we had r-12, the real duPont freon, which I still use today)
I have fallen victim to this issue as well. I went over everything, evap system, wrapped my muffler in a heat mat 3 times with a heat shield. Did just about everything. And then it dawned on me. About a year ago when I was redoing the whole fuel delivery system, I used a Airtex fuel pump
I have had the same problem but the last time it shut down I thought it was the fuel pump over heating. Up to that point I had replaced many parts and looked at everything I could think of. So long story short after pulling the Airtex pump out and putting a new Delphi pump back in it still did not work. That is when I found it had blown the fuse for the pump and the problem was the sensor (fuel pump/oil pressure sender/switch) was shorted out. I looked into the wire diagrams for this and found that the fuel pump fuse is tied into this circuit. Since I changed this sensor (its next to the oil filter) I have not had a problem in over a year. I hope this helps and works for you.
I have had the same problem but the last time it shut down I thought it was the fuel pump over heating. Up to that point I had replaced many parts and looked at everything I could think of. So long story short after pulling the Airtex pump out and putting a new Delphi pump back in it still did not work. That is when I found it had blown the fuse for the pump and the problem was the sensor (fuel pump/oil pressure sender/switch) was shorted out. I looked into the wire diagrams for this and found that the fuel pump fuse is tied into this circuit. Since I changed this sensor (its next to the oil filter) I have not had a problem in over a year. I hope this helps and works for you.
Oil pressure switch. And it's at the rear china wall, no where near the filter.
I have had the same problem but the last time it shut down I thought it was the fuel pump over heating. Up to that point I had replaced many parts and looked at everything I could think of. So long story short after pulling the Airtex pump out and putting a new Delphi pump back in it still did not work. That is when I found it had blown the fuse for the pump and the problem was the sensor (fuel pump/oil pressure sender/switch) was shorted out. I looked into the wire diagrams for this and found that the fuel pump fuse is tied into this circuit. Since I changed this sensor (its next to the oil filter) I have not had a problem in over a year. I hope this helps and works for you.
What exactly were your symptoms in a nut shell? I can drive the car for about an hour in this FL heat nonstop until the pump starts acting up. Anything above half a tank and it'll keep on going. Recently It'll occasionally whine even after a cold start but doesn't affect drive-ability. Nights I can go as long as I want without the pump making a sound. When I put the Airtex in about a year ago I never had this issue. I guess it's ran it's course. Ordered a AC Delco so we'll see.
The sensor is above the oil filter. And according to my 89 Pontiac Service Manual it is called a fuel pump/oil pressure sender/switch. I dont care if you believe me or not. My car is running great since I changed it. I had all the same problems this thread has talked about for years and my problem has not been back in over a year and a half. So good luck out there.
The sensor is above the oil filter. And according to my 89 Pontiac Service Manual it is called a fuel pump/oil pressure sender/switch. I dont care if you believe me or not. My car is running great since I changed it. I had all the same problems this thread has talked about for years and my problem has not been back in over a year and a half. So good luck out there.
Hahaha. Your contradicting yourself. You said sensor and now you read the service manual and said sender/switch. You also said "next to filter and now said above filter. So now it sounds good. Just giving you a hard time man. I know plenty. I did a full rebuild of my engine in 09. So I'm familiar with the nuts, bolts, sensors, and applications.
I had an idea about not letting the fuel reach the fuel rails (where it soaks engine heat) only to return back to the tank with heated fuel. But no one took my idea serious and it has been lost in the servers. But oh well.
What exactly were your symptoms in a nut shell? I can drive the car for about an hour in this FL heat nonstop until the pump starts acting up. Anything above half a tank and it'll keep on going. Recently It'll occasionally whine even after a cold start but doesn't affect drive-ability. Nights I can go as long as I want without the pump making a sound. When I put the Airtex in about a year ago I never had this issue. I guess it's ran it's course. Ordered a AC Delco so we'll see.
You just described the same problem I was dealing with. When it stopped running that night it had the Airtex pump in it. I changed it because my buddy owns a Car Quest Store and he told me they stopped selling Airtex pumps for GM cars because they were having too many problems. So Car Quest changed back to using Delphi pumps only for GM cars. I had him get me a new one and it still did not work. My bad for not checking for power first but it was a blessing in disguise, because it lead me to the sensor problem and I never looked back since. I have put a thousand miles on the car over the last year and a half and she is runnig great. Hope this helps.
You just described the same problem I was dealing with. When it stopped running that night it had the Airtex pump in it. I changed it because my buddy owns a Car Quest Store and he told me they stopped selling Airtex pumps for GM cars because they were having too many problems. So Car Quest changed back to using Delphi pumps only for GM cars. I had him get me a new one and it still did not work. My bad for not checking for power first but it was a blessing in disguise, because it lead me to the sensor problem and I never looked back since. I have put a thousand miles on the car over the last year and a half and she is runnig great. Hope this helps.
Forgive me for being so specific. But when you say after the fuel pump change that it didn't work do you mean you still had drive-ability issues or was your car not starting?
Forgive me for being so specific. But when you say after the fuel pump change that it didn't work do you mean you still had drive-ability issues or was your car not starting?
Just that I did not have power to the fuel pump. Since changing the sensor I have not had any problems. Car runs great.
Its funny I just swapped my fuel pump today and fuel pump wasn't working after everything and wasn't getting a SES light when key first on engine off. Turns out I smomehow blew the ECM/FP fuse right next to the battery. Was trying to kill the FP and get the pressure out of the lines. Still lost about a gallon or two of*gas.
As far as the pump goes I used a AC Delco Ep241 pump to replace the Airtex. I can't even hear the pump whereas the Airtex made a loud whine when first priming. I think my problems with the FP are over. But I will update in the event something happens
Figured I was the only one who would ever have had a problem with fuel temp. Guess I was 15 pages wrong!
Not sure what I can add, but vehicle started running very poorly, normally after being shut off and restarted. Would even do it in near freezing temps, and never been anywhere warmer than maybe 85*. Symptoms are extremely rough idle, potential stalling, noxious exhaust.
Got a LOT of modifications from an 80's Camaro, Vortec heads, Headers, different cam, etc. But huge engine bay, and 31 gallon fuel tank..
Was checking injector resistance, noticed fuel rail was too hot to touch, even after sitting for a few minutes. Hit it with a temp tester, it was 145*, the intake was 160*. Had the hood up, so not like it was heat soaking from that. Fuel pressure pretty rock solid at 25PSI, holds no pressure when shut off. Going to verify it's pump vs. regulator keeping pressure down, then go from there.
I now know some have had issues with fuel line routing heating up the fuel tank, I'm going to see if I can measure the tank temp.
IMO, in my case, the pump isn't moving enough fuel to suck the heat out of the rails. Same reason GM eventually went to a return system on the carbed setups...deadheaded, the fuel got too hot.
Edit: People should think long and hard about their problems. Yes, fuel line routing (if the car is modified in any way) can be an issue, however in my case, it was flow. Tank hose was split from pump to sending unit, was leaking pressure and thus volume. Loss of flow means slower and less fuel returned to the tank, meaning whatever does get back to the tank will be "super heated".
And if it wasn't clear, the problem was the leaking fuel hose. Low-volume of fuel=increased fuel rail heat. With low pressure/flow (25PSI), rail was at 145*, which is too hot to touch for prolonged period.. After replacing hose and pressure/flow at stock (43.5PSI) the rails remain cold enough to touch at all times. Did not actually measure them, but it is a noticeable difference. Not to mention the problem is gone.
Last edited by dyeager535; 12-23-2014 at 11:01 AM.
Moldman, you out there ? I'm trying to replace my sensor as I have had the same problems you had.
The dealer ordered one for me and it turned out to be a single wire sender. Ordered another one and it looked sorta alright except it was a 3 wire, mine is a 2 wire and no, someone did not cut out the third wire. The plug doesn't have a hole for a third wire. Do your remember if yours was 2 or 3 wire and possibly the part number ? Thanks for any help !
Just want to update. Been just over a year since my dreaded fuel pump issues and swapping to the AC Delco pump. Not a single problem. Been in stop traffic on a hot day with just under quarter of a tank and it kept on running. Where the old pump would have left me in the middle of the road. So for me it was the fuel pump.
So the dealer tells me that my part is discontinued, but gives me the part number. Ended up getting one from Oreillys and instead of $50 or $85 that the dealer wanted for the 2 that didn't fit, it was less than $13. If anyone is interested, the part is a Borg Warner part, # S4060
Just want to update. Been just over a year since my dreaded fuel pump issues and swapping to the AC Delco pump. Not a single problem. Been in stop traffic on a hot day with just under quarter of a tank and it kept on running. Where the old pump would have left me in the middle of the road. So for me it was the fuel pump.
Haven't had any issues with it at all? How about whine? I have the ACDelco installed and the thing whines like a jet in anything above 60° weather.
Not a peep from it. Just replaced it or been in there awhile?
Replaced it last April right before my engine swap. Did some research on here and ordered a new Bosch unit that comes highly recommended. Apparently the ACDelco pump sounding like a jet and eventually going out is very common. Hope it fixes it.
Has anyone solved this? I am dealing with extremely high tank pressure and a whine coming from the engine compartment, the fuel is so hot it makes the injectors rap in a random pattern. While running, if I loosen the gas cap vapor rushes out continually until it stalls.
Has anyone solved this? I am dealing with extremely high tank pressure and a whine coming from the engine compartment, the fuel is so hot it makes the injectors rap in a random pattern. While running, if I loosen the gas cap vapor rushes out continually until it stalls.
I went with the Bosch. Its VERY quiet. Hasn't been that hot yet though
This is obviously an old thread, but it seems that the brand of Fuel pump wasn't thoroughly investigated between everyone contributing...airtex? bosch?
With the ethanol corn fuel used today vs the old fuel, the type of fuel might have been a culprit--might suggest a tank of super 92 octane, and not have the pump fall below 1/4 tank, as the fuel cools these submerged pumps.
Has anyone solved this? I am dealing with extremely high tank pressure and a whine coming from the engine compartment, the fuel is so hot it makes the injectors rap in a random pattern. While running, if I loosen the gas cap vapor rushes out continually until it stalls.
I had this issue a while back- turned out to be the vapor line to the Charcoal Canister was pinched off. The Vapor system is designed to release pressure/fumes to the cannister once the tank reaches 2 psi, but it sounds like your's is not doing so. IIRC, the stock system also has a pressure relief valve at the tank, but since mine is a conversion, I don't have that or knowledge of it.
I would detach the rubber hose coming from the tank to the canister, before the check valve, and see if you get the same pressure issue there. If so, the check valve may be bad, or the canister may be plugged.
my formula did the same thing. Couldn't figure it out and NO repair shop could figure it out...always after driving for an hour it would do the SAME EXACT THING. finally on a whim, i replaced the ignition control module in the distributor...BOOM, fixed.
In my case, it was definitely the fuel pump. I've been close to E a few times in FL heat and it's been going strong. I do have a high pressure release when I loosen the gas cap on a hot day but I don't have a canister and have the vent line capped off with a vented gas cap. Thinking about putting it back in since changing the fuel pump as I thought the canister was a possible culprit.
I've been chasing this bloody thing for 12 years. Also, look under your plenums at the small black plastic tubes. One of them controls the purge solenoid on the canister. I had a hole burned through mine. The canister will pass the GM diagnostic because it does not take these hoses into account. My purge could not open as that hole was a vacuum leak. But again, it will test fine. With that valve not opening, the tank will not vent. I did not drive a lot last year but when I did it was hot out and I did not have a repeat of the problem.
Well my problem has yet again reared it's ugly head. Stalled out on me yesterday after a 200 kilometer drive. I started noticing a problem when I got on it merging onto a freeway. It wouldn't pull past 4000 RPM. 15 minutes latter, on a side street thankfully, it shut down. Tank was pressurized. I've been through 5 fuel pumps from Walbro, Holley to China, and my issue never changed. For me it's not fuel pump related. I've attributed this to exhaust heat. It's the only possibility left. I have an 80 series Flowmaster sitting inches from the gas tank, with the factory shield in place. The tank actually gets so warm that it's uncomfortable to touch. I've ordered a flowmaster heat shield and a Thermotec heat shield to install on the factory heat shield. At this point I should be able to re-enter the earths atmosphere and survive it. Beyond this, I have no idea what to do next. Shell 91 has no Ethanol in Canada, so it's not that either.
"At this point I should be able to re-enter the earths atmosphere and survive it"
I'll check at the thermal department here at NASA and see what they have!
Back to topic. I, like most here have this same problem FOR 27 YEARS. I am perplexed that this has not been remedied yet. There are 1000's of post' on this and still no definitive answer.
"At this point I should be able to re-enter the earths atmosphere and survive it"
I'll check at the thermal department here at NASA and see what they have!
Back to topic. I, like most here have this same problem FOR 27 YEARS. I am perplexed that this has not been remedied yet. There are 1000's of post' on this and still no definitive answer.
standing by............
I'm perplexed to say the least. I do know that the symptoms are the same every time it happens. A hot fuel blast from the tank. I did however notice my vacuum line was knocked off. The very one that controls the purge solenoid on the canister. I just found it. I must have done that when I set my timing two days ago. The vacuum tree is right below and too the left of the distributor (looking at it) right beside the external coil. I've mentioned this vacuum line in previous posts. In the past, I found a hole burned in it to the point it welded it shut. This line prevents the gas tank from venting to the canister if it can't open the purge valve. Regardless, I am still going to insulate that reactor hanging beneath my tank. If the fuel starts bubbling and off gassing then the pump starts to cavitate. Which means it's not going to push fuel through the lines.
Put in a new sending unit- the rollover valve is clogged. Replace the pump, filter and vapor system while you are at it. No car should have 25 yr old fuel system components in it. Get a piece of adhesive heat shield for the top of the muffler shield if you want.
Bosch Pump- $40
Sending assy- $100
Filter- $10
New hoses- $10
Canister & purge valve- $60 / $20
Not being in a Car-b-que- priceless. Your car is a rolling bomb right now- fix it!
Be sure all the frame lines are clear before reassembly and use new rubber hoses on the new sending assy and everywhere else!
Put in a new sending unit- the rollover valve is clogged. Replace the pump, filter and vapor system while you are at it. No car should have 25 yr old fuel system components in it. Get a piece of adhesive heat shield for the top of the muffler shield if you want.
Bosch Pump- $40
Sending assy- $100
Filter- $10
New hoses- $10
Canister & purge valve- $60 / $20
Not being in a Car-b-que- priceless. Your car is a rolling bomb right now- fix it!
Be sure all the frame lines are clear before reassembly and use new rubber hoses on the new sending assy and everywhere else!
I cut that rollover valve in half, pulled out one check ball, enlarged the hole to as big as i could, and drilled the tree smaller ones to 3/16, then epoxied it back together. I have pictures of what I did in earlier posts. The lines are clear, I blew them all out. The system is sound.
"At this point I should be able to re-enter the earths atmosphere and survive it"
I'll check at the thermal department here at NASA and see what they have!
Back to topic. I, like most here have this same problem FOR 27 YEARS. I am perplexed that this has not been remedied yet. There are 1000's of post' on this and still no definitive answer.
standing by............
really? on all your 3rd gens?
I wonder if those who have run them every day do not have this issue
Oh Bob I dont want my car to blow up!!
not to mention being at a stop and having to rev engine to keep it up and running.. and restarting sometimes.. doesnt have that cool factor
Drove around for 15 minutes yesterday. Ambient temp was 19 Celsius. Shut the car off and after 5 minutes, the muffler was 82 Celsius (180 Fahrenheit) and the gas tank was 42 Celsius ( 108 Fahrenheit). Definitely some heat transfer there. My last break down happened after 200 kilometers of back road driving. I didn't have a thermometer, but I'd bet the tank was well above 42.
Sounds like an assignment for all of us to do. I'm gonna run up the road this weekend and get half Pure non ethanol and half 110 Racing fuel (it smells like grapes) and see how that goes.
I just drove my 88 to work; 22 miles, ran like a raped ape, freeway speeds of 65-75 and low speeds 25-45. Got out of car and walked away. It didn't blow up yet.
We have a couple of gas stations that sell pure gas non ethanol. I switched to non ethanol and after two tanks full all my problems went away.
I'm running pure gas. No ethanol and I still have the problem. It's a 100% tank temp and venting issue. That's the one constant every time this happens. It's usually during a left turn, sitting in the middle of a 4 lane intersection during rush hour. I'm going to have to look at the left turn indicator as well.
I'm running pure gas. No ethanol and I still have the problem. It's a 100% tank temp and venting issue. That's the one constant every time this happens. It's usually during a left turn, sitting in the middle of a 4 lane intersection during rush hour. I'm going to have to look at the left turn indicator as well.
LOL. you do that
Good to know you have it with pure gas but bad as well. everyone let us know Maybe we should start a voting thread about type of gas with comments about idle
06-12-2013, 09:32 PM
I'm perplexed to say the least. I do know that the symptoms are the same every time it happens. A hot fuel blast from the tank. I did however notice my vacuum line was knocked off. The very one that controls the purge solenoid on the canister. I just found it. I must have done that when I set my timing two days ago. The vacuum tree is right below and too the left of the distributor (looking at it) right beside the external coil. I've mentioned this vacuum line in previous posts. In the past, I found a hole burned in it to the point it welded it shut. This line prevents the gas tank from venting to the canister if it can't open the purge valve. Regardless, I am still going to insulate that reactor hanging beneath my tank. If the fuel starts bubbling and off gassing then the pump starts to cavitate. Which means it's not going to push fuel through the lines. 
