Hey guys. Just recently picked up a 92 TBI RS about a month ago. To make a long story short, the person I bought it from was the second owner and bought it from the dealership back in 97 with only 17,000 miles on the clock. Since then he rarely drove it, and at one point it was garaged for one full year - I didn't get into detail whether he started it every now and then or not. Fluids were not drained. There was some gunk in the coolant because of this, but I cleaned that out already. When I drove out of the seller's driveway, it had 55K miles on the clock. Since I have bought it, the oil has been changed, radiator flushed and refilled with new fluid, coolant emptied and changed, and the diff serviced also. I have not done a tune up, nor do I know when the last time it's had one. Probably never. This is #1 on my list of priorites as soon as I get paid, as well as servicing the tranny. The car is basically stock (performance wise) except an Edelbrock open element and a Flowmaster 40 series muffler.

Now, onto the noise. Obviously it is a very clean car inside and out, due to it being rarely driven. The engine runs strong and sounds great, but when I am accelerating there is a very, very faint "gargling" noise that I hear. It seems to do it only on a slightly heavier load (small hills / uphill) from what I can notice. My friend who also has a 92 TBI RS with 198K on the clock, his engine also makes this noise, but it is MUCH louder and noticable. On my car it can only be heard when it's quiet and the windows are down.

My 87 LG4 LT (159K miles) also makes this noise. What exactly is this? EGR valve being plugged full of build up? That is just a wild guess. The reason I doubt that is the problem for my RS is because I usually only hear of the EGR valve starting to get plugged on higher mileage engines (at least 100K+). And so you know, I haven't had a chance or the time to personally look at/check/attempt to unclog the EGR valve. What I've been told is, if the EGR valve is plugged, you can open it an the car wont stall. If it is not clogged, then the car will stall when you open the valve.

If any of you are familiar with this noise and have any feedback to offer about the problem or any comments to correct any info I have given, I would appreciate it. Thanks

-Jeremy

 

Change fuel filter and see what happens. I know when the car doesn't get enough fuel it'll make that sound.

Does it sound kinda like when you don't give it enough gas on carburated engines?

 

The only thing I can think of is maybe an injector hung wide open or what you are hearing is knock. Do you know what knock sounds like. Try to run a mid grade gas and see if you still hear it. Also, look at the injectors as they spray and see if there is a nice conical shape without any drips to the fuel pattern.

 

Guess I'll give that a go, see what happens. As for the noise you're describing, not really familiar with it.

I thought a higher octane on a mostly stock L03 with the base 0* timing will slow it down because of an incomplete burn, as you stated in the "New to TBI" thread. I was running 87 octane in my 87 LT for a while, and it was making tons of noises. For the past few weeks I've been adding 92 octane, and added some Lucas with a full tank and changed the oil, and it's completely quiet now - no weird noises at all. So maybe the higher octane will help in my RS, but I don't want the car to run slower at all. Maybe try 89? Would like more feedback from you before I do this. As for knock, not TOO familiar with that term or noise, but I'm pretty sure that's what my LT was doing before I put in the 92 oct.

 

I have to use 91 or higher, otherwise I get the ping. I know higher octane burns cooler, therefore preventing the knock or ping you hear, but I don't know what causes it in the first place.

 

I would try 89. Even with base 0* timing you can have ping if you get a bad load of fuel or if you have carbon deposits in your egnine. These carbon deposits get super hot and can pre-ignite the intake charge and cause knock. However, since your car has such low miles I doubt this is the problem. You usually see that problem with cars that have well over 100k miles. Your car should only have large amounts of carbon depsosits if the EGR never shut or you had some other problme that caused the car to run right all of the time. I would still try 89 and see what happens. Some stock TBI cars cannot run 87. Fuels are slightly different state to state and they may not have their exact advertised ocatane. Do not use the Lucas junk. The stuff they make is only a band aid for cars that are on their last leg. We run 89 octane in one of my dads work trucks (305 TBI with 0* base) because it will knock really bad with anything less. However, it has 150k miles and have an extensive amount of depsosits that are causing the knock.

 

If its more like a gurgle or a popping its probably the exaust. If the car hasnt had a tuneup in a bit this could certainly be the explanation. Detonation will either be a pinging sound or if its real bad detonation, it makes a sort of metallic 'FWACK!' sound. Best way I can describe it. If it was well and truly detonating youd hear it loud and clear over everything else. I had an olds that would do something similar. 3300 w/ mpfi/MAF etc with only ~70,000 miles on it so it was in almost new shape but it would always make a faint popping or burble when it was idling. Sort of like a lean miss almost. I imagine with a flowmaster that noise would be alot more pronounced, and at WOT ive heard alot of flowmasters make that rapping noise in a near stock motor. On top of that, teh baffles in a flowmaster like to rot out so they loose their ability to control exaust noise. Most people like to say theyre breaking in but really theyre jsut turning into hollow rusty cans.

Oh, if you want to clean out the combustion chambers, the water trick works quite nicely. Just make sure you drop the cat because the freed deposites could plug it up.

 

I'd also say it could definitely be your exhaust. You have very low miles on an old car. I bought my car in similar condition 91 with 57k miles on it. When I got it, I thought it was louder than it should be, turned out the intermediate pipe was rotted through and cracked in a couple places. I assumed this to be from such little mileage in that amount of time that water built up in the pipes and erroded them. Check out your pipes, make sure you don't have a leak. Mine was cracked on the top of the pipe that crosses over the axle.

 

What water trick?

 

You spray a mist of water into the TBI while the car is running and the steam will help disslodge any carbo buildup in there. Make sure your cat is dissconnected because some big chunkcs could plug it up.

 

I actually used a pitcher of water. I opened up the throttle some and poured in enough that the motor complained but not so much that it hydrolocked it. Lots of steam, some water, and a mess of carbon deposites came out. Did the same thing to my vortec 4.3. Similar results.

 

Did the car run much better after that? I may have to try that on my dads 305 TBI work truck. It is so carboned up it needs 89 to keep from pinging with 0* timing.

 

Not noticably so. It got the deposites out but there probably wasnt enough in there to cause problems to begin with.

 

I still kinda want to try it for kicks and giggles. I geuss it can't hurt. And a cleaner engine is always good.

 

The car does not make this noise at idle, it is only when I start giving it more gas around 25mph. From a stop when the car first starts accelerating, I don't believe it makes this noise - or maybe I am not paying enough attention. I'll have to double-check tomorrow. I just started noticing the noise a few days ago. It's when the car is already moving.

Also, the "FWACK!" is more of an accurate description of the noise over gurgle. It's more like "kack-ack-ack-ack" really faintly, just for a few seconds as the car is picking up in speed as I'm giving it more gas. As said, my friend's 92 TBI Camaro also makes this noise, we have the same exact cars - except his has considerably more miles (197K), and he has a Magnaflow instead of the Flowmaster. But that noise on his car is much more noticable.

I'm also pretty sure it's not the exhaust, but NOT positive that couldn't be the culprit. It sounds like a noise that's coming from the engine. Another reason I don't think it's the exhaust is because my 87 LT which has a stock exhaust, and has been driven basically daily it's whole life, also has made this noise.

 

Could it be the exhaust's heat shield?

 

I still think it is knock since you hear it when the engine is under load. Try some higher octane and see what happens.

 

What is the "water" trick?

 

Never mind. I just saw it....

 

The "fwack-ack-ack" sound you hear, is it like marbles in a jar, sort of? Mine was pinging like crazy after I advanced the timing, and it sounded like what you are describing...

 

What kinds of oil pressure readings are you getting?

 

Just out of curiosity, why do the car texts in your above posts apear as links? Where you trying to link something? Donno, maybe I just picked up some adware or something thats doing it.

Anyway, If its more of a metallic ping sound like maybe something small repeatedly hitting the block then it may be detonation. If you want a good example of it, listen for the older late 90's ford cars and minivans with V6's. That metallic sound they make is detonation. Maybe its the gas around here but I could swear those things run entirly on detonation. I dont hear anything in my car over the exaust except soccer moms in a hurry. Can hear them coming a mile away. 'PINGPINGTINGTINGPINGPING..PINGPINGPPINGTINGING'. Dont know how those motors last as long as they do. Heard one guy in a 6 cyl crustang and that thing took the 'three rocks in a coffee can' to a whole new level. Ive never heard detonation like that, and jsut about every one of those 6'ers seems to do it when its hot out. Crappy fords... Its better with the bowtie.

 

If it's more of a ping it's detonation, if it's a gargle that is perfectly normal.

 

What causes the gargle?

 

my car gargles after I LET OFF the gas... hmmm

 

Thats fuel being burned off with too little timing. Increasing the timing in those areas eliminates it.

 

Just wanted to say thanks to everyone that's responded to this topic.

The noise I have been hearing is knock. As I mentioned, my friend's 92 TBI RS makes the noise, but it is much louder compared to what my Camaro was doing. The reason his knocks so much louder is because his timing is advanced 8*.

The reason my <A TITLE="Click for more information about car" STYLE="text-decoration: none; border-bottom: medium solid green;" HREF="http://search.targetwords.com/u.search?x=5977|1||||cars|AA1VDw">car</A> was barely making the noise was probably because a bad load of gas or something from that station. I have not been hearing it recently, but I will start running 89 if the noise returns as you advised, Shifty.

Also, the reason why the car text in my posts are links is because I picked up some sort of <A TITLE="Click for more information about spyware" STYLE="text-decoration: none; border-bottom: medium solid green;" HREF="http://messagebroadcaster.net/bannerfarm/link/sw/sw.htm">spyware</A>. Damn savages.

 

I am glad it is knock and not something worse. Tell your buddy to take back some of that timing to around 4 or 6. He is not any good having it that high. Also, you may want to try the water cleaning trick to clean out some carbon deposits in the motor. That way you coulf get away with 87 again.

Oh and go to www.download.com and download Spybot. It will take care of that spyware in a heartbeat.

 

Ad-aware is also a reasonably good program, although some of it is so bad you have to remove it by hand, especially those browser highjacking programs. I would like to take those people that make that stuff and bludgeon them to death with a sledge hammer

 

The gargle that you hear, does it sound like blowing bubbles into a glass of water or whatever through a straw?

And since you said you can only hear it inside the car, you might have a problem with the tank pressure control valve, or a bad evac cannister, the gargle would be the tank relieveing pressure.

 

I told him to turn it down some because it makes the <A TITLE="Click for more information about car" STYLE="text-decoration: none; border-bottom: medium solid green;" HREF="http://search.targetwords.com/u.search?x=5977|1||||cars|AA1VDw">car</A> knock pretty bad, but he says when he turns it down he gets sh!tty gas mileage. Any advice there? It's not even my car and it annoys the heck out of me. It's so loud, that if I'm driving his car where there's a bunch of pedestrians, they all look with a "WTF?" expression on their face. lol

It sounded exactly like what interfac9 described: marbles rattling in a glass jar, which was knock. My case wasn't that severe, as you could barely hear it, but 89 octane fixed the problem.

 

Wow I couldn't even quote you because of the span interfereance. Anywhoo, your friend is killin ghis motor at the expense of a few MPG. I doubt he is getting better fuel mileage as well. He needs to back off the timing. I could plug my fuel line and get more miles per gallon but I think you get the point. Tell your friend that.

 

89 firebird formula. my car is stock besides the fact that it has, headers exhaust and a shift kit. what grade gas would i run? is 87 ok...i hope so..its expensive now.

 

sure its not the torque converter staying in lockup? that will cause the car to bog down and "gargle" when going up small hills, etc.

 

87 octane is fine. If you run the factory 0° base you won't have any problems with ping.

 

cool, i was thinking that but..figured id run it by everyone else