i have 1990m olds cutlas supreme 3.1 v6. i have replaced the map sensor the o2 sensor and the plugs and wires and i have checked the fuel pressure and it says its fine but when i step on the gas it just loses all power if you could please help me . i took out the 02 sensor and started the car to see if my cat was clogged but it still did the same thing


(This post was edited by dsteelman on Mar 23, 2008, 3:01 PM)

Possibly a restricted exhaust system as in a plugged catalytic converter?

Dan.

Canadian "EH"

i took out the 02 sensor and started the car and it still had no power

I understand your thinking that removing the O2 should relieve the back pressure of a restricted system but it may not be enough? Dropping the system off of the rear manifold would defiantly confirm whether there was a restriction. Plus that would also allow the 02 to remain connected.
Have you performed an engine compression test; ensuring that general engine condition is ok?
Check engine manifold vacuum; it should be around 18 to 20 inches of mercury and fairly steady at idle. A significant drop in vacuum and a fast vacuum gauge reading recovery; when you snap the throttle open and closed.
Have you checked that there is a strong vacuum supply to the map sensor? The hard plastic vacuum lines that feed vacuum to the sensor can crack & leak.
If all of the above is ok then it might be time to have a scanner connected to the PCM? Not just to read codes but to monitor sensor data and how the PCM reacts to the data.

Dan.

Canadian "EH"