O.K. I just bought an 87 gn about 3-4 weeks ago and did the spring cleaning. when i bought the car it ran fine(boosted up too 15psi, shifted fine) just all around ran well. But that has not been the case in the last week, my maf and O2 sensors went out and after i got those fixed i am getting a rough idle and code 44, but the main problem is when i get on it it boosts up to about 14-15 and BAM!!! it sounds like it backfires. What is that?? I have an aftermarket boost gauge so i know the boost is right.
thanks for any help!
From what I've heard/read/been told, getting a good reman'd MAF is a crapshoot. Chances are the new one you got is bad. Take it back and get another one. See this http://www.gnttype.org/discus/messages/37/2408.html?1059241826
O2 sensors are an item that does have to be replaced so depending on when it was last changed and if any leaded gas was used, this may be a typical thing. I've been running leaded fuel in my car and a new O2 lasts about 3 weeks, maybe 4.
My friends GN was doing that last night. I thought it was the coil pack. I would like to hear what the "gurus" say.
FWIW, you can upgrade to the newer style MAF sensors with the translator from www.ramchargers.com.
Also, Denso has a new o2 sensor that is supposed to last a lot longer with leaded fuel:
http://www.turbobuick.com/forums/showthread.php?threadid=65765&referrerid=0
Check the hose under turbo, the one that goes to the wastegate and see if it has burned thru. Also tap the maf sensor with engine running and see is the rpms change. A good rebuilt maf sensor is hard to find.