Ok so my flex pipe has had a big hole in it for a while now and i decided to get it fixed. I had welded a new one on and also installed a test pipe in place of my cat and at first the car ran good for like 2 minutes after warm up. since then it runs like @!#$ out of boost and has a sporatic idle. Theres black smoke shooting out the exhaust. I had disabled the 4 codes for the rear o2 sensor and unplugged it thinking that would help but it didnt. My narrowband air fuel gauge no longer lights up when the engine is running. It is still functional because it lights up when i turn the ignition on. Now i had logged a run with hp tuners after doing this and the LTFT AND STFT gauge was reading in the red zone on the vcm scanner. I have a log file if someone wants to see it, just tell me how to post it. I need help with this very badly and any help is much appreciated.
01' Z24 5 speed
422whp/400wtq
T4 Turbocharged
Built LD9
HP Tuners
sounds like you killed your upstream O2 sensor and it's dumping a ridiculous amount of fuel in
but that's just a guess
2001 Olds Alero (LD9)
650 whp / 543 ft-lb
@turboalero
yeah i have to agree with above....the rear o2 just lets the ecm know the cat is working. somehow the upstream o2 must be screwed up.
well i was using a torch to heat the header cuz it had a kink in it and i reshaped it with a hammer. the torch might of screwed it up
01' Z24 5 speed
422whp/400wtq
T4 Turbocharged
Built LD9
HP Tuners
no wideband but it was the front o2 after all. i put a new one in and it runs like a champ. it actually runs better without a cat now.... odd
01' Z24 5 speed
422whp/400wtq
T4 Turbocharged
Built LD9
HP Tuners
