Engine starts great, idles smooth. It bogs down & backfires at 2000 rpm. Installed new timing belt, cleaned EGR ports in manifold. No change. The manifold pressure at MAP sensor is reversed from what it should be. I have low vacuum at idle & high vacuum at higher rpm. (MAP sensor output actually decreases as I increase rpm). Worse News is I have check engine light & I can't pull the codes. I've tried by using a jumper with no luck. Auto Zone, Advance, O- Riley's say their stuff won't go back to '94 & they can't pull the codes. PLEASE HELP> I'm almost wishing I had a Ford.

 

See DIY section on ECU/TCU/ABS codes procedure. This is fastest way to solve your problem.

good luck

 

Thanks for the feedback but, I said that there are NO codes. The clue was that the check engine light is on. Haynes repair manual says that if you have check engine light with no codes, it's the ECM. And that's what it was. Bought a ECM on e-Bay. Fixed it. She's running like a pickle seeder. (that means running great)

 

Glad you fixed it!

I interpreted your original posting as not being able to pull the codes and referred to procedure.

good luck