Well, just ran into my first problem with this car in it's 28 years...

Idles and runs really choppy randomly. Finally it set a pair of codes: 33 and 45.

33 is for MAF high voltage and 45 is rich O2 sensor.

Can I assume that one is causing the other? O2 sensor is probably around 10 years old with maybe 8,000 miles on it. I'll check for obvious vacuum leaks and electrical connections when I have some proper lighting.

Any other words of wisdom?

 

Checking the O² sensor activity in a propane flame is one way to verify it can make a good signal. Of course, it has to be removed to be tested. The high MAF flow/voltage may be be coincidental, but a vacuum leak will typically contribute to the conditions required to set a 32 (low MAF flow/voltage) and not high MAF. Just for the sake of argument, what is the TPS voltage at the closed-throttle position?

And since there is at least one common part of the circuit that may affect both, the ECM and engine grounds, it may be good to verify good grounding as well.

 

Does anyone know what: code 44 is on1991 5.0 TBI camaro