Hey guys I am so close to getting my Firebird back running for the first time in 25 months. Anyways here is the run down. The car has a lt4 hotcam with 1.6 gm roller rockers out of the hotcam kit. I have a lt4 knock module. I also have a hotcam tune from Trifeca tuning. Anyways in start up the car runs like a champ in open loop. As soon as the car goes into closed loop it miss fires and will even stall out. I was working on it a couple weeks ago when I was home as I am 100 miles away at college and it had this problem so I ordered a new set of ac delco oxygen sensors. Even with the new oxygen sensors. I am stumped on it at the moment. So what could cause the car to run perfect in open loop then horrible in closed loop. I have checked for intake leaks and there is currently no exhaust except long tube headers. It would still act up when it had exhaust on it. Any Ideas as I would like to actually have a running car again.

 

Codes? scan it.

 

No codes at all. Scanned it three times. Even with running. Even ran it for a while and still no codes. Working on up loading some videos.

 

Ok here are some videos.

This is the car in open loop
http://www.youtube.com/watch?v=XXaKln1oXnk

Here is the car in closed loop.
http://www.youtube.com/watch?v=j151FXwHHVY

I also changed the coolant temp for the ecu. No change.