I recently bought a co-workers car thinking I could make a quick few bucks. Well that was wrong so far.
Basically, when I got the car it sounded horrible, the engine jumps and shakes idling, and had about 20 mph top speed.
We changed the plugs, coil packs, checked the wires to see if they carried a spark. Still nothing.
So then we pressure tested each cylinder thinking we might have a blown gasket, all cylinders were around 150-170 PSI
So then we changed the fuel filter, nothing. Pulled some injectors from another car, put them in it, still the same!
We decided the engine might not be able to breathe, we cut the catalytic converter off, and now the car will do all of 35 maybe 40 mph.
And basically we're stumped. If anyone has any ideas, I'd appreciate it. The engine is throwing a check engine light (although it could've be catalyst), but the way its running theres no way I could get it somewhere with a computer. And it has no plates.
What engine is this? I'd guess maybe throttle position sensor.
Shoot. Not TPS, the Crank position sensor.
Wouldn't that throw a check engine light? Right now all thats up is P0300
I don't think so. Then again, I could be wrong but that is what comes to mind. You've covered most of the other things, so that pretty much leaves the CPS, or the computer itself.
vacuum line as well.
maybe not today, maybe not tomorrow....... but some day
Maybe the computer is damaged
Or, of course a Mime could be in the trunk.
My wife's 2003 Ecotec 2.2 liter Sunfire:
* 2 1/4 inch in and dual 2 inch out muffler Trans Am muffler
* 2 1/4 piping to a very long 2 1/4 inch resonator
* 2 1/4 inch catalytic converter
* an AEM true cold air intake NOPI edition
* 8 gauge ground wire kit
* Toyz front strut brace
* Russell stainless steel brake lines all around.
Sounds like a vacuum line is the culprit to me. Probably compressing when the car is running but looks fine otherwise. Several posts in here about the symptoms you describe.
Good luck
