I have a 1991 Trans Am 305 with 5 spd. No mods.

The car surges from 1000 to 600 rpm for several times then runs smooth. Then 30 sec. later it surges a few times and then smooths out again.

I brought it to my mechanic after the car would keep killing as I went to neutral while driving.

He changed some items: EGR valve, module, oxygen sensor,and AIC. He checked the TPS and it was OK.

Now the car does not kill anymore, but the surging is still there.

I ran some fuel cleaner through it, but no change.

I've brought it back to him, but he says these cars just tend to run this way and that he can't find anything wrong.

Is this something I have to live with. Sometimes it is so rough and surging that I get a stomache ach!

Any experience with this problem, please contact me.

------------------
Sean

1977 S/E TA
1980 Conv. Turbo TA
1989 TTA
1991 Conv. TA

 

No, it's not normal...you need to find a mech that will plug into the car with a scan tool, monitor the CTS to start with.

Disconnect the IAC, see if it quit's surging, if it does, then have him look for item that control the IAC counts.

You may also want to have the TB thoughly cleaned.

 

A tune-up is in order...if not fixed then vaccum check...look around the driver side, intake manifold, around the vaccum tube coming out which goes to the pcv valve. Last check would be fuel pump psi/pressure reg....

V/R,
Frank

 

Thanks for the responses.

I cleaned the throttle body with some spray cleaner. Sprayed it in till it came out clear. I did this through the front blades with the TB still on the engine.

I also changed the hose to the PCV valve. And the PCV valve too.

My mechanic checked the computer with a scan tool. He found no trouble codes.

The IAC has been changed.

Still have the problem.

The car runs very strong and smooth when driving. It just has this bad idle.

He has the car and is going to run a scan again tomorrow.

Will update tomorrow.

------------------
Sean

1977 S/E TA
1980 Conv. Turbo TA
1989 TTA
1991 Conv. TA

 

My car does the same I have changed just about everything. but my car will idle from like 750 to 900 and to 550 around there and it will smooth out for maybe 5 seconds and will die again. please update

------------------
91 Z28 5.7l Camaro
T-56,McLeod Street Clutch, Cross Drilled Brakes, KYB's,AFPR, 3.73 Gears, Borla Adjustable Cat Back, Hypertech Chip, Hooker Headers.
more to come....
My 91 Z28

 

Hi Chris,

Does it die al the time or just some times? Mine used to die before I had the work mentioned above done to it. Now at least it will keep running.

Just don't get in if you get motion sick.

I will post any findings tomorrow.

------------------
Sean

1977 S/E TA
1980 Conv. Turbo TA
1989 TTA
1991 Conv. TA