My 87 convertible is not behaving itself.
All of the leads and plugs are new. The running temp is normal and the airways are clear.A code 36 was showing and the engine had a miss and seemed to be running rich. I have now changed the MAF burn-off relay and the engine runs perfctly, the miss seems to have gone. HOWEVER, the car doesnt like starting from cold, and when shes warmed up.....she stalls when i shift into gear. It will stall maybe 6 or 7 times and then itll be fine all of a sudden. Ive been under the car to check the earths to the bell housing and they are fine. The car never sees bad weather so there isnt any muck down there...or anywhere for that matter. Despite the problems, there arent any codes showing.
The tick-over is 800 rpm...is this about right? If i adjust the tick-over up to the 1000 rpm mark, the stalling seems to be worse. At 800 rpm the engine does put up a bit of a fight before cutting out.
Somebody please help me before i set fire to it!

 

On the 85-88 vettes there is a CSV (cold start valve or 9th injector). If you are having problems starting the car when the engine temp is below 100* then I would check that first. The symptoms would be having to crank it a few times (on the first start of the day) for it to start running, but will start fine when the engine is warm. If you would like more detail on how the CSV works let me know. There is a thermal switch and a fuse that operate the CSV and is powered by the starter solenoid and not the ECM.

The stalling will most likely be the ignition module in the distrubitor, since you state the plugs and wires are new. You didn't mention about the IM (can be tested free at autozone). You might want to ohm the injectors cold and hot and have a fuel pressure guage handy when the stalling starts to rule out a fuel problem.

 

 

For $6 I'd run a can of SeaFoam through it, this stuff works wonders. If I still had the problem after that I'd pull the IAC, clean the passages, then either clean or replace the IAC, new IACs with gasket are about $35. You may also want to check for any vacumn leaks.

 

Autozone, SeaFoam and IACs with gasket about $35! Ask this guy where he's from!

 

Sounds like a fellow Brit

 

Hey guys thank you all for your posts......yes im a Brit....North Wales to be exact.
I have just today replaced theIAC valve for a new one. The old one was completely jammed. The car started from cold very well, which it hasnt done for a long time. As the battery had been disconnected, i took the car for a run to let the ECM "re-learn". I covered about 7 miles and i hav to say...the car has never performed so well for me. Great acceleration and no misses or back firing which was a problem before. When i got the car home i switched off and waited a few minutes...started her up, shifted into gear....stall...ugh! Its weard..if i give it a little throttle when i shift into gear it will go fine..and then any shifts i make after that from neutral to drive are fine. Its as though ive conned the car! However, ive run the car since to check for vacuum leaks (cant find any), gone back to it 20 mins later so the engine is still hot...start her up and she shifts into gear fine. I dont want to tempt fate, but ity is going into gear every time without stalling. Is the ECM still learning? When i first start up from hot the revs go up to about 1300rpm and then settle to 700rpm...is this right?

 

Have you checked the voltage at the TPS?

 

Yes ive done that and it is correct....0.54v exactly.