I have a 1991 firebird t-top with a 3.1 engine.

In the firebird, when started it has to be jumped off by another vehicle, (battery will be replaced this Saturday.) The headlights are mounted/incorrectly angled when pulled up. The previous owner said the timing is off, and it also looks very worn.

The main issue with the car is when sitting at idle, unless a driver is pressing the gas a little bit, it will stall within seconds, you cannot brake or completely come to a stop unless you want to stall, and cut off.

The previous owner states that he has replaced several parts to include the fuel pump, fuel lines from tank to engine.

Any suggestions/diagrams that can be provided would be greatly apprechiated, I've got several from autozone.com, but any others that you have would be awesome.

 

Also, it is a automatic..

Thanks for your help.

 

Also, where can I get just plain vacuum lines to replace all the vacuum hoses in the car? I've found sites that have hoses, but they arn't just several feet to where I can take it and use it for the whole car. They are just ones that are bent and about 1' long and cost $4 and some change. Or will I need some of those if I am replacing all of the lines?

I have talked to others in my shop at work and they said at advance and autozone.. But I havn't been able to get up there yet to check.

Do I need any certain lines for any areas in the engine or can it all be the same for the whole engine bay?

 

Start by correcting the timing. You should be able to buy vacuum hose in bulk at most auto parts stores. While you're replacing vacuum lines, look around for any place there could be a leak.

 

I already have the timing chain and just waiting until tomorrow when I have more time to replace the chain. Is there anywhere I can find a diagram of the vacuum lines.

 

Yup.

I know that autozone sells various sizes by the foot, as I have bought some.

 

One cool way to do the vacuum lines without buying a ton of hose you dont need is to drive the car to the parts store and just remove one line at a time, take it inside, match it up, replace it with new. Work through all the vacuum lines this way. There are several different sizes of hose used on an engine. Some may be a different size on either end. Youll have to get creative with hose adapters to replace these or just buy OE replacements.

There are many possible causes for a stall. Does the engine run rough or just idle low?

 

Cant really drive it up to autozone unfortunately due to it stalling out, but I'm going to be taking the car and taking off every hose I see and physically inspect it and probably replace all the hoses I can find in the car.

ASE doc, it runs rough and you can hear it trying to stall out while just idling but now if you even take your foot off the gas, it will stall out within about 10 seconds, whereas about 2 weeks ago, it sat there idling for about 5 mins..

 

Is this motor TBI? Im sorry I dont know. If it is, watch the spray pattern from the fuel injectors at idle. It should be a wide conical(cone shaped) pattern. On throttle snap it should hit the sides of the throttle bore and create a mist. If the spray pattern seems wimpy, you may have a broken pressure regulator spring. The spring is exposed to atmosphere and can rust and eventually crumble to pieces. Fuel pressure should be about 13psi on a gauge at idle.

If its port fuel injected, fuel pressure could still be an issue. Connect a gauge. Pressure should be 35 at idle and jump to 40 on throttle snap.

Connect a scanner to the ALDL(the 12 pin connector under the dash, below the steering wheel). Watch data while you keep the engine running. What is TPS voltage? MAP voltage? TPS should be about .5v at idle. MAP should be around 1.3-1.7 at idle. If either are way off you will need to test the circuits for them.

Mitchell on demand or All Data is available at your local library and each has the test procedures and diagrams for these sensors

BTW, I never answered your question regarding vacuum diagrams. The emissions diagram should be under the hood. If its missing, you can get a diagram on Mitchell or All Data. Most repair manuals will also have the diagram. Helms publishing printed the factory manual. Its like a bible for anyone working on these cars. You should be able to order a manual through them. Otherwise, a Chiltons or Haynes will work in a pinch.

 

Oh, also I dont know if its just I'm missing something or I'm not really sure what. But, where is the timing chain at on a v6 189 engine? I've looked just about anywhere I could think, and dont see it. I'd imagine it would be sitting right on the front of the engine but.. its just not there.

Also, honestly I'm not positive but I do not believe it is TBI, and could I just "rent" tools from advance auto parts or napa to go home, test the parts or would I have to pay them to test it for me or how could that work?

I've been debating getting Mitchell but I'm not sure yet, (I will probably give in in like.. this weekend probably lol)

 

The timing chain is at the front of the engine inside the timing cover. Replacing it is not a small job. Definitely get on Mitchell On Demand and study the engine section well before starting. Print pages and have them with you while you do the job.

Why do you think you need to replace the timing chain? I wouldn't go there unless youve proven that its a problem.

First perform a compression test, then follow with a leak down test. The compression test will verify low compression which could be caused by valve timing. The leak down test will verify that compression loss isnt a bad valve or rings. Then connect a timing light and look for fluctuation in timing while you snap and release the throttle. Timing should advance and retard smoothly with engine speed. Any "wobble" indicates a loose timing chain.

Last, using a socket and breaker handle, rotate the crankshaft back and forth while observing the dist rotor (youll have to have the cap off for this). The rotor should turn with the crank as you turn it back and forth. A few degrees lash is okay but anymore than 5 degrees indicates a worn chain.