With the MAF unplugged the car will stumble at first and then run fine. If you have no real change unplugged the MAF is not the problem. P0171 is the biggest pain in the world to find and fix. Most of the time it'* a vacuum leak. After seeing all you have done, I'm starting to think it'* a vacuum leak in the HVAC system. And talk about a pain to locate. You said you swapped out the FPR because you could smell gas in the vacuum line? Check it again to make sure your not having the same problem. Because a leaking FPR will cause the very problems you have.
SAVING THE WORLD ONE BONNEVILLE AT A TIME
1997,1998,2000,2005 year confused Bonneville SSExi. Stock? ish.
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