OT Chevy Lumina

On a Chevy, basically you short two terminals in the OBD connector under the dash with a paperclip, turn the key to the run position but don't start the engine, and count the flashes on the check engine light. OBD-1 Fords have a similar procedure but use voltage pulses out of an underhood diagnostic connector instead of flashing the check engine light.

Good luck. I seem to remember that there are a few things that'll cause it to run rich or go into limp-home mode but won't set a trouble code, but its been long enough since I owned an OBD-I Chevy that I don't remember the details.

Keith

PS...Haynes, Chiltons, etc. will have the diagnostic codes in their repair manuals also. Most libraries have them.

A "general" rule of thumb is to always look at the lowest trouble code first.

I don't think that car is going into loop since you're showing both a 44 and a 45 as well as the 33. Is the temp sensor plugged in? The one with the black/yellow w/black tracer colored wires?

The computer control of the fuel system kicks in at 151 degrees. If the computer cannot see that temp, it just "throws fuel" at the engine to keep it going.

I'd clear all the codes, take it out for a spin and see which code trips the light first and concentrate on that area.

Hope ya get it,

Allan

• GM trouble codes

The worst thing you can do is just start throwin' parts at it because the problem could be anything from a plugged air filter to an O2 sensor to a thermostat (yes thermostat).

From what you say, it sounds as though it is in "limp to the hospital" mode, which means that the computer is just throwing fuel at it to keep it running.

It needs to be properly diagonised by first having the trouble codes read and a trouble tree ran.

Just my opinion,

Allan