There has been much discussion here (including myself) regarding stalling problems with the 2.2. My 1996 Sunfire 2.2 has suffered this problem for several months now - never throwing a check engine light or any codes. It seems many of us were unable to locate the source of the problem. I, like many others, had replaced all the 'suspect' and 'likely' parts without correcting the problem.
For those of you still trying to fix this, and like me have already replaced most or all ignition parts, fuel parts, sensors, vacuum lines, etc, here is what actually fixed mine.
After much wire poking and prodding I was able to locate an intermittent wiring fault. The fuel injectors have 5 wires - 1 wire signal/ground from each injector to the PCM, and 1 common 12V power supply that splits to supply each injector. The 12V power wire was intermittent at the main engine harness split at the most inaccessible location - just below the heater core hoses, at the rear of the block left side (just above and to the left of the ignition coils). Basically the injector 5 wires join a sub harness with the MAP, IAC and TPS wires, then run down to the main harness. It was where this sub harness (about 20 wires) joined into the larger main harness where the intermittent was.
As it was not possible to reach and repair this wire without engine removal, I spliced in a new wire and ran it separately (in a new protective sheath) from just below the injector connector at the left of the intake manifold, to the main harness at the front left of the engine where it was much more accessible. What was happening was that as the engine moved slightly under varying loads, all injectors were losing the 12V power supply and the engine would just quit - at any speed. If it reconnected quick enough - it would catch itself and not stall. Other wise it normally would start right back up again. The connection was generally 'good' in engine off condition - hence the normal restart without problems. Once I found the right stop to poke, I could stall the engine at will, and if I kept tension on the harness, it would not restart.
With the new bypass wire installed - all is now normal again.
It was very time consuming to first locate, open the harness protective sheaths, then to determine how to repair, and locate the correct wire in the main harness. Hopefully anyone who is unable to fix this problem may benefit from this experience.
Mike
Good info. Mike.
Thanks for posting
Alont
1998 Cavalier 2.2L - STALLING / MISFIRE / ENGINE LIGHT - Hope its not a dead cylinder. Bad Plugs?
My car began barely running on like 3 cylinders. I'm not quite exactly sure whats going on. She's misfiring bad. I'm thinking it may have something to do with the fuel filter. Like stalling and hesitating/jerking at intersections. I gotta rev her up just to keep it going. I need some help. Would some one suggest what's going on? I'm able to provide more detail. This happened before and I replaced both oxygen sensors. I don't know whats going on. Could some one help me please? Bad Plugs perhaps?
Mike, my sincere appreciation for your sharing ...
You'll never know how much anguish and expense you've saved others ...
Thanks again !
