Join Date: Mar 2012
Gideon is offline
95 S10, missing, running rough, no power - please help!
Hi everyone. I've tried everything and hoping that you folks have heard of this issue.
1995 Chevy s10, 2.2 engine with about 100K miles.
This is my dad's tru8ck and he was driving and it suddenly started to run rough. He got home and I looked it over, and it seemed to be fine, but still running rough.
I changed the spark plug wires, and plugs - and it ran a little better but still rough at idle and would not rev over about 2K. when I press the gas, I can hear it trying, but it acts like a governor - it'll rev up a little then the power just drops out and it starts to fluxuate up and down sort of like it's not getting fuel. under load it runs smooth and does not miss - but only to about a quarter throttle then it's it - it starts to idle up and down and I have to back off.
I've checked - so far...
Coils - replaced them both. Got a third and swapped them just to be sure.
Wires/plugs as well. (new plugs quickly carboned up)
Fuel pressure is in range and solid.
Cat converter is clear and no backpressure issues.
Fuel regulator clear, clean and dry.
No codes. Not even a missfire code (using a paperclip)
Replaced the MAP sensor just for the help of it.
Cylinder pressure test - a-ok.
My mechanic says that all PCM numbers come out okay, and that the PCM is communicating correctly. No codes, all sensors read within tolerances, and he says it's not misfiring - just running rough and weak as a wet noodle.
I've not checked the mechanical timing because of the whole cover off thing - I'll save that chore for last thing, I think.
I did notice that there are two sensors on the passenger side in front of the coil, one high and one lower and slightly further back (that one is not plugged in, not sure what it is and can't find a plug to fit it)
Thanks in advance.
Mechanic couldn't check the mechanical timing.
. I also had to replace one of the coils, and that helped as well, and now it runs great on all cylinders - but still