Which means one of the sensors inside the sensor broke. Time to replace the MAF.

Well Mike, I just installed Fel-Pro seal kits for both the intake manifold (since I was seeing some seepage) and the intake plenum. After 5 mi, I got the 171 again, but no 102. And the trans is actin up. Is my next step to replace the MAF or oxygen sensor? The MAF is a Delphi. Should I do an exact replacement, or will any work? I see the China version is $39, and a new Delphi is $94. Can I voltage check the MAF? BTW, How does one reset the PCM? I have never done that. Thanks for your patience.

I told you to replace the MAF from the get go. And no, stay away from the cheap chinese crap. You will only run into more issues.

You need to reset the PCM by using your scantool to "clear" the codes.

Mike -- by 'PCM' I thought you were referring to a "Powertrain Control Module'. I refer to the computer as the 'ECM' (Engine Control Module), which I have been re-setting as I go. Why does fixing the 171 code have to be such a guessing game? Can a GM shop find the solution faster and cheaper?

PCM, ECM, they are both the same. Next year they should be calling it ICM. Idiot Control Module.

What have you done to fix the P0171?

I should receive a new MAF sensor Thurs --- a Delphi AF10126. I see the original was not a Delphi, as I had told you, but an 'AFH50M-05' -- made in Japan. I can't see any obvious broken wires. I am not holding out much hope for that as a fix. I am regretting not checking the fuel pressure.

Fuel pressure has nothing to do with the MAF sensor. I'd like to know where your getting your info from.

Hello Mike -- Sorry for the delay -- My computer got hit by the hackers.
Replaced the MAF sensor with a Delphi (stamped: made in China) and my 171 went away! Also, my tranny is acting fine. Now on to a fuel sending unit problem -- will replace pump and all. Any cautions here?
Years ago, I told myself that keeping any vehicle longer than 10 years is asking for trouble, but they aren't making Park Aves anymore, and this one only has 130K.
Thanks for the help --

ac delco or delphi pumps last longer and work better there as well, and if it comes with a new plug be sure to use it and solder/heat shrink the connections. no connectors the vibration of the car will cause intermittent issues down the road.

How to Test the MAF Sensor: P0100, P0101, P0102, P0103

or
Part 1 -How to Test the MAF Sensor GM 3.1L, 3.3L, 3.8L (1989-1996)