Jet

Hello, i have a 91 Camaro RS 3.1 V6 Engine Stock. 88,000 miles on engine

My Problem is when im on the hiway and give it half or third throttle it die's with no warning, its like i turned off the switch, sometimes i can throw it in neutral and it will start back up but most of the time it wont start at all and strands me on side of the road. Last month i had to Tow it home then the next day it fired right up but after driving it a few miles it stalled on me again but after sitting on the road side for 30min it started back up and got me home, it seems to run fine if i just baby it and not give it much gas but soon as i give it half throttle it just dies on me.

I have owned the car for over 2 years and it never gave me any problems at all, i drove it from california to AZ and back with no troble at all, i have put about 10,000 miles on it since i bought it but this new problem just croped up out of nowhere.

I replaced the fuel filter but that did not fix it. Lord i hope its not the fuel pump. i cant replace it myself and i know its gonna be alot of $$$ since the rear end has to be dropped and tank has to come off.

melsplace6

Sorry, I'm haveing similar problem only now it won't run but for about 2 or 3 seconds. Started to do what you mention and I babied it home. If you can hear the fuel pump get your self a fuel pressure guage and check pressure, should be around 40psi or better. I pulled the plugs and they were fouled, so I put new ones in--------it started an run for a few minutes an then died. back to square one. I replaced Iac, tpc, fuel pump, fuel filter and now thinking of replacing injectors. You can check injectors with a noid light but it won't tell you what the ecm is telling how much fuel to dispense. I hope I am answering my own question. Good luck. post your solution if you find one.

RS Reaper

wow this is freaking me out. I have the same problem but mine is a 90. Worked fine early this week but then yesterday it gave out wouldn't start. Replaced plug, cap, and wires thinking it was the cap and replaced the other stuff cause it was old. It now can idel but is stalling under pressure. Fuel pump is not even a year old. My grandfather and father who were both mecanics at one time say that there best guess is the fuel. I'm replacing my fuel filter now so guess we well see.

Hey! What state you guys in and what was the gas sation that you last fill up at?

melsplace6

Check fuel pressure first, save your money on filter. If just one injector is bad, the ecm will try to compensate with a different fuel mixture (rich or lean) check your plugs. I'm in the middle of rebuilding two 454's on my boat so I quit screwing with the camaro for right now but plan to tackle the problem shortly. Might be a good idea to check ignition module first but I still think my problem is injector.

RS Reaper

ok probably a stupid question. How do I check fuel pressure?

melsplace6

Live in Washington state, was just at Fort Benning. Gas at Arco was 2.60

RS Reaper

ok have not replace the fuel filter but i did just drain my car of gas. the smell is not strong and i'm pretty sure there is water in it. Have to wait till morning to see if it separates.

melsplace6

test port for the fuel is just behind the cross air inlet, it has a cap threaded onto it like a tire fill stem. Pressure guages are generally inexpensive at any auto store or borrow one from some one who you might thing has one. Our problem I think will be the fuel injectors, ------------or not========= one way or the other, I will find the solution!!!!!!!!!!
----------
Tell your dad and grand dad to get out there and help you. Four heads are better than one. My 91 is actually for my son who is in boot camp in GA and I wanted to have it running when he graduates.

RS Reaper

ok tested it and it is fine. drained the fuel and put in fuel filter (had some trash in it) and then filled it back up with new fuel. Still not working. My dad and grandfather are both helping me but there as puzzeled as we are. Also there more of old school guys. they are better with carbs then FI. Guessing now is to check exhaust.

RS Reaper

Ok checked the exhaust to make sure it was not pinched and it's fine. Finally got a code on the scanner and it was 33 or the MAP sensor. I changed it out and reset the computer and now the car try to turn over and just can't get there. Looked back in my recorders and found out that a very simaler thing happen about 5 years back and it turn out to be the computer. Getting new computer tommrow. Hope that works.

one2burn

Hi I have a 91 v6 with a start runs fine but wont accelerate check out my threads I finaly got a code 13 after nursing it up to 2500rpm for a few minutes parked. I searched the words code 13 in the forums. Its helpful. You might want to search on yours before getting the ecm. Can you post what you find, Thanks George.

RS Reaper

conditions for a code 33
1) engine under 2000 RPM,
2) MAF reading over 45 gms/sec, and
3) less than 25% throotle.

lol well that was funny lots of good stuff but every ones got there own winner so here is a list of what they did.
1. Someone burn his own Eproms and said it took care of the problem (raised the error threshold from 45gps to 55)
2. replaced the MAF relay and the "burnoff" relay
3. Replace temp sensor
4. THROTTLE POSITION SENSOR
5. replacing the harness connectors to temp sensor
and much much much more...not kidding.

Also people have had it where they can't drive there car for years because of this. I'm not happy as this is my DD.

Ok call me crazy but I'm going to go for a temp sensor then a Throttle positiong sensor if that doesn't work well not happy but haven't spent that much.
-edit-
i have not yet put in the computer

Jet

Well it's probably not the ECM because when i bought the car 2 years ago i had GM put in a brand new ecm. insterment cluster. and Cat converter. and and few sensors witch i cant remember what sensors they put in but anyway how long does an ECM Last? surly more then 2 years at the price they cost and are so vital to every thing that keeps the engine running.

this cost me $854 and i think the ecm was why it cost so much they are pricy.

PS... This problem did pop up just an hour after i let the tank get VERY LOW on gas, the lowest it has ever been since i owned the car for 2 years. so yeah im sure it picked up some trash, i bought my gas in California in a small town called Farmersville from some mini mart with gas pumps because gas was chepest there at the time, another thing is when i barly made it to that gas station and got my gas i was on my way to a smog check station, it passed the smog and 10 miles later on my way home on the freeway is when it all started, i thought ok maybe the guy at Shell who did the smog check knocked something loose. vacum line or something but i went over it and everything looked good.

anyone know how long the ECM last?

OldCelica

I had my Wife's 91 Camaro start doing this a little over a year ago. It did turn out to be the fuel pump. It would run fine for weeks at a time at first. The issue kept getting more frequent. Try carrying a fuel pressure gauge with you. This way when it stops running you can check it when the car is not able to run. You can get a code 33 just because it idles crappy enough to meet all the conditions above.

RS Reaper

Was not the computer.
while I feel that reprogramming it would work i feel that is more just covering up the problem.

Going to try the THROTTLE POSITION SENSOR tomorrow.

one2burn

Did you have that computer tested ?

Jet

Let me know how the THROTTLE POSITION SENSOR works out, if it works for you it might work for me, if not i will probaly go with the feul pump next.

today i went to 2 defrient autozones and the first guy said it was the Knock sensor, the other guy said it was the Throttle position sensor and if it was the fuel pump it would not run at all.

i think the knock sensor was what GM replaced 2 years ago so im going with throttle position sensor first then fuel pump

Thanks guys for replaying to my post, i douted i would even get 1 replay but so fare the information has been very helpfull at narrowing down the problem.

RS Reaper

not the old one but the new one was.

one2burn

Hi just a little update I have checked codes, fuel pressure, timing, mufflers, there is now a new cat (yard took cat out) and o2 sensor, fuel filter, new ing. module, cap - rotor - wires & plugs - Tps sensor, now I have to say I just replaced all that stuff for gp anyway because I got this car out of a junk yard. The other day I did have a code 13 come up after deciding I would hold the Rpms up for a while just to get motor to running temp. Then went to start it up today coldest day so far and could not get it to start right up like it always had so it left me wondering if the fuel was all that bad left in there but as I thought about it figured it could'nt be fuel problem I've got a Quarter tank in it of good fuel and it had next to nothing in it to start with. Well anyway I believe my ecm is ok because it gave me the 13 and now it dosen't it after installing o2 sensor - gave the code for unhooking the loop wire for checking timing and if there were any other out of range things having to do with any of the sensors well there's codes that come up for that. Today after getting it started and letting it sit there to warm up as it dropped down to the final idle point right at that moment it came on with the cooling fan an obvious problem since it was no where near hot enough for that yet. I unpluged the fan switch next to the the thermostat but no change so that lead me to the spot where someone had cut across the fan wires and twisted them toghther pulled one side apart to stop the fan and let it warm up to check o2 sensor at aprox. 600 degs. seems like went to closed loop no codes everything running smooth just fine, temp guage ok went up to about 200deg. and I nursed it out of the driveway went up and down the street (flat ground) and parked it because no change it still wants to die under any quick acceleration. Now the fan thing could be a sign of problem in the ecm/chip or just a bad switch but the not starting right up thing today makes me think possible week ing. Coil because I don't think that would give a code and as far as the stalling it might also be the problem but I am more leaning to side of the Map sensor even though I have not had any codes for that it dies right out if you crack the throttle as if though it is not reading the change in manifold vacume, the line to is is just fine and motor vacume is ok to. Once again though it could be the Ecm/chip not reading the map or Tps. Funny after typing this out to you I just was thinking about a guy who brought me his corvette that had a same starting problem once in a while that got worse with a lean running cond. every once in a while that lead to dying every so often that got worse and a fan that came on when it shouldn't you know I sent him to the dealer because I thought the ECM/ chip might be bad to many things wrong at once. Sure enough it was a bad prom chip they replaced it and all problems solved hard to believe but it ran fine after that. Well hate to put you through reading all that but I'll let you know how it all works out, Thanks for your come back, let me know how you do, George.

RS Reaper

Was not the computer. I ended up meeting this old car guy that gave me a number to this garage. Turn out the number is to a guy and his work is great; he has fix a bunch of hard car problem for a lot of people around here. So I drop my car off at his garage and he said he will fix her for $150. Hope he well fix it and I can get back on the road. I'll post what mine turns out to be.

one2burn

So I started out this morning checking CTS and found it was right in the the resistance range no prob. with it but I did find that the voltage comming to it was 4v and should have been 5v, put on a new coil tried to start cold and no change, drained fuel and put 5 gal. premium chevron no change still. Leaves me to think only two things possible left fuel pressure reg. or the ECM/Chip. let you know. Thanks again, George.

one2burn

Just to let anyone know out there that the service manual lets you know that you should see a 3 - 10 pound drop in fuel psi after car is started and running, mines staying at 42 I will be checking Fuel pressure regulator tomorrow let you know what I find, 91 3.1 v6

RS Reaper

Hey guys. Wanted to update you guys on what I found and see what you guys found. Turns out, there was a few wires that were chewed up they have been replaced and then turns out that my distributor was rusted and I really can't believe that this cause there is no other rust on this car but it is 17 years old and that has been replaced now. Also now the engine runs really smooth can't wait to get her out. Only got one more problem. Now she runs but in about 5 to 10 mins of idle and the engine cuts off and doesn't throw any codes. Any help would be great.

Jet

Thanks for the update, keep us posted...

i took a chance and drove my car about 12 miles to get gas, i filled her up and she would not start. i had to push her away from the pumps and sit 2 hours while it cooled down, after that she started and got me home.

PS... i had a new can of starter fluid with me just incase but it did Not help, i i sprayed some in there and it would start for about 2 seconds then die, i tryed this about 10 times in defrient ways and non worked, i thought ok once it starts i'll just pump the gas and keep it running but Nope didn't work.

SO the car will not start after warming up. and will die if i give it half throttle or more then it wont start till it cools down, its not overheating or anything like that, it idle's fine when starting up in the morning and will drive fine just so i dont give it much throttle, but once i drive it and warm it up i can not turn it off or i will be stuck for 2-4 hours, in the hot summer though's hours will go up im sure. seems like its not getting gas up there. starter fluid would start it but not keep it running.

five7kid

iTrader: (14)

If it would start with starting fluid but wouldn't stay running, that's a very good indication it isn't getting fuel. That can either be due to the fuel pump not providing pressure, or the injectors not firing. Heat can be the cause of either one.

You need to find out what your fuel pressure is doing when the engine acts up. The other possibility is getting a "noid light", a way to test whether or not the injectors are getting their proper signal. It's 99% that it's one of those two.

one2burn

Hi thanks for the info, mine needed a timing chain to start with and I found a injector that would not read any ohm's across the terminals all the others 11 or 12 the fuel pressure regulator was strecthed out of shape from sitting dry to long hence no drop in the psi. after starting but yours sounds I guess to be something that gets hot and quits possible fuel pump - ing. module - ing. coil or even ECM or Chip. Oh ya and check your grounds they get hot and don't work as well esp. if dirty/rusty.

Jet

Ok tomorrow im gonna buy a Fuel Pressure Gauge and drive it a few miles in a Circle around the block to warm it up good, i dont want to get to fare from home, after it warms up good i will park it turn it off and try to start it again, if it dont start i will check Fuel Pressure. i'll post back what i find out.

im thinking i need a new Fuel pump.

RS Reaper

Hey sup guys. Well the guy still can't get the car to stop shutting off it's own injectors. So the guy has given me an idea on what is making it happen. He said it is the security system is clicking on for no reason and is probably shutting down Injectors. Wanted to see what you guys thought. If this doesn't work I'm sorry to say I'll have to package her up and let her sit till I get the money to continue fixing her.

Jet

I never thought about the security system, i guess anything is possible at this point.

i havent yet got around to getting a Fuel Pressure Gauge, im thinking i might just take it to this local shop around the corner and let them check it for me, if i dont get this fixed in a few months i might have to let my baby go for something that RUNS.. where i live if my car is not drivable it will get towed and i really cant work on it here either.

i will probabaly end up putting her in the shop for a new fuel pump and strainer. if that dont fix it i might have to let her go.

what ever happends i will post my results

one2burn

I have a 91rs 3.1 v6 that would start, run, no codes, as soon as you crack the throttle it would die. Things I checked before replacing ECM, Fuel Psi., timing, coolant temp. sensor., Tps, Iac Solonoid, Things I just replaced for GP because I got this Car from a junk yard, Ing. Module, Dist. rotor and cap cleaned rust off contact points under rotor, Plugs and wires, fuel filter, drained and filled tank 5 gall. prem., found a lot of play in the chain and changed it both gears and damper, fuel psi would not drop after starting changed fuel psi. regulator fine now and found one bad injector mine all read 11 to 12 ohms. but one, book says anything below 8 is bad. New Cat and clear pipes/muffs. Even got a code 13 once and changed O2 sensor and found knock sensor wire disconnected and hooked it up. So now after all that no change but as I read in the book I found a line that said that in the event of a ecm failure the cooling fan goes on to save from over heating. Bingo as soon as the car came down off of high Idle from cold start the fan kicked on. so that left me to thinking is it the ECM or Chip. I guess you have to think about the two like this when your dealing with them, Chips are the brains and the ECM is the body and the body is what more often gives out first, so I'm so glad this one did'nt have DE DE DE also.

Jet

maybe you have found your problem.

my fan seems to be working properly, it only comes on after the car warms up realy good or sitting long time at red lights. i took it out yesterday and drove it about 30 miles, the last 15 miles it started trying to die when ever i give it gas but i found out if i let off the gas soon as i loose power it will catch up and i can gently give it gas and get my speed back up but if i let it die im sure i will be stranded a few hours til it cools off. this is realy a pain, if only i new for sure what the problem was i would not mind spending so much money to fix it, but i dont have money to throw at every part hopeing i fix the right one.

RS Reaper

Just got off the phone with the guy again and guess what? It now turns out I got some lines and stuff going to and from the fuel pump that are worn and stuff. They’re going to change those out before they go clipping wires. I hope that works I really would like to keep the chip system in for security reasons.

one2burn

That throttle responce problem is the same thing I was having even after everything I had done and checked on it the New ECM cured it for me I did have a good chip I Had to use it in the New ECM.

Jet

Since my ecm and chip are only 2 years old im thinking i have to go with Fuel Pump, well a few hours ago i went to Napa and got OEM Fuel Pump and Strainer Total=$84, At 9:30AM tomorrow im taking it to the carlot where i bought the car, the guy will put in the pump and let me make payments for what ever the labor cost is. im gonna look at the gas lines to because RS Reaper may be onto something there as well.

so soon as he fixes it i will post back, should only be a few days.

god i hope this fixes the problem

one2burn

I guess you all ready have replaced the filter but if it has been a good while I would check it out again before the pump

BthomasM

Hey guys, I've got the SAME problem with my 1990 3.1 also, i've replaced just about everything it could be, I've even got a friend thats a corvette specialist that's been helping me out with this crap and he can't figure it out either. I've been researching this problem for weeks now and I have found that this is a common problem with these engines. I know someone out there has fixed this problem before, I just wish one of them would say something about it!

one2burn

Hi, mine was the ECM, my chip was ok had to use it in the new ECM and it worked fine. Check out my threads, went threw everything to including VATS to just to get the car out of the junk yard.

BthomasM

Where is the ECM? If it's in the computer then I've already replaced the computer, I just did that this morning and I'm still having problems. It seems to run a little rough when I first start it up, but as soon as it reaches temp. it dies when I rev it up a little.

Jet

I think the ECM is the computer. ECM=Electronic Control Module

on my 91 RS 3.1 it is on passenger side under glovebox, ok there really isn't a glovebox but you know what i mean. you will have to take out a few plastic screws and remove panal.

PS.. My car is in the shop, i just went to look at it this morning and they have been working on it, should be done by end of today, i will post back weather or not the Fuel Pump Solved my probleme or not...

five7kid

iTrader: (14)

ECM is the computer, but it stands for "Engine Control Module".

4th gens started controlling the transmission electronically as well, so it became the PCM, "Powertrain Control Module".

BthomasM

Well I kinda figured that, but I just wanted to make sure. Thanks

RS Reaper

Well the fuel lines were not the problem. I got to say I am quite happy with this guy even tho he has not fixed it yet. He seems to get more excited and stubborn that he will find out how to fix it every time something doesn't work. His comment to me was that "It is kicking his butt but I will find out how to fix it." Also I found out he has a 1992 V8 camaro so he has work on these before.

melsplace6

Okay, a little update. I finally got time to work on the camaro. I replaced the fuel injectors that I bought reconditioned for 35.00 a piece and the fuel pressure regulator and installed. Car runs awesome now. Hope this helps someone.

Jet

melsplace6

Thanks for the update. im glad you can drive again...

for my update, my car is still in the shop, 3 weeks now, put in new fuel pump and strainer, car still dies and wont start after it warms up. put in new Distributor Cap and Rotor Still same problem. they are working on finding the problem and thats all i know for now. i will post back when i have any more input.

melsplace6

Sorry your car is not running. I did extensive research on my problem and it sounds alot like yours. That particular year of camaro has an inherent problem with injectors. Just one bad one will cause the ecm to send signals to the other injectors to compensate and make the car run so rich that it wont run at all. Check your fuel pressure and if its around 42 psi then you will know its not your fuel supply. I recommend replaceing all the injectors and the fuel pressure regulator.----------If you can get a noid light, check that all the injectors are getting a signal. Its a long process, but since you replaced the fuel pump and filter, you might as well keep going. As stated earlier with my problem, I had no codes that indicated any problems with IAC or TPC sensors or anything else for that matter.

Jet

the shop checked it and the fuel pressure is fine, injectors and plugs/plug wires are all good, i dont know if they used a noid lite or how they did it, but i also need to tell them check the fan and switch because i hear that if the fan dont come on when the car warms up good the ecm will shut off the fuel pump and kill the engine to save it from blowing up. right now they are checking the fuel pressure regulator, i will also ask them to check the fuel pressure right when it stalls to see if the ecm has turned off the fuel pump, umm i guess there wont be any pressure if the ecm shuts off the pump?,

i do remember while smoging the car the fan took awhile to come on, the guy even said it was a little hot and might have to abort the test, right when he said that the fan kicked on and it passed the smog, then 10 miles down freeway is when it all started, so the fan might have died shortly after the smog, just a guess.

rgarcia63

Check the fan wiring for hacking, also check the fan relays
I know One2burn said he read that the ECM will disable the Fuel pump if the fan don't work to keep the engine from burning up if it overheats. I would like to know what book that was in.
I do know the V8s are programmed to turn on the fan at temps as high as 225°F. There's also a bypass high temp circuit that the ECM doesn't control to turn on the primary fan, or the secondary fan at 238°F if the ECM fan driver circuit malfunctions.

RS Reaper

Sup guys. Well still have not got my Camaro fixed. The guy had it for about a month. I finally got tired of waiting and when to find out what the deal was and the guy told me he couldn't fix it. According to him he fixed some chewed up wiring and put a new distributor in. He claimed that he went through the wiring harness but I don't believe him. When I when to get it the steering Column was messed up, the tilt for the wheel is broken and now when you pull it the wheel drop into your lap and now part of the blinker stick pulls out. Both were not like that when I put it in the shop. That pissed me the most off; I had it with this guy. I'm going to find out how much it will cost me to fix the column and take out of the bill he gave me. I then decided to take it to a guy I know through my dad. The guy said that the wiring was messing up and that it needs new injectors. When he told me that injectors would run around $130 for each I about died. Luckily he agreed to use the parts I would supply; that I get a discount on and for fun guess how much they are.....$36.56 each....talk about mark up. So I am keeping my fingers cross, I really need this back on the road.

melsplace6

Make sure and replace pressure regulator while your at it. shouldn't cost more than 40.00. Mine still running great.

RS Reaper

Wooo..I'm back in black. lol cheesy...I know.
Turn out that 4 injector were pretty much dead basically was running off 2 cylinders if you believe that. Not bad for a 175K car with stock injectors. It took the guy less then a day to figure it out and fix it everything, got all new injectors and stuff. Very strange as my fuel pressure was fine but she is now running, smother and with more horses then ever. Now I got to go pay the bills that have mounted up for this car this month; good thing I love this car.