Help!!! CODES AND LOADING UP BAD
 

Ive been having this problem for a little while and need to fix it now. I have a check engine light and codes are for p0300 random misfire, secondary air at maximum threshold, and dead o2 sensors in bank #2. The symptoms are when car is starting to warm up from a somewhat cold engine, under slight to moderate throttle, the motor boggs and seems like the cat is clogged or is loading up really bad. Then in order to stop this, I have to either rev the crap out of it or accelerate. It continues to bog till about 3-3500rpm then launches like hell. It seems to have had this problem ever since my 02 wires melted on my headers. Fixed the wires and the problem went away for a little while although the check engine light stayed on. I looked at my 02's on my scanner and they were sitting ducks up and down steam on bank 2. Also the motor boggs down to 400-500rpm coming to a stop or sitting at a red light. Belive its the EGR. Anyone that has heard of a problem similiar to this or any ideas please help me out. Sending to GM dealership at last cost. Thank You

Jason

So, did you replace the 02 sensor that is giving you problems?

when my o2s were bad they did that exactly i bet if you get a scanner and check it while you are driving whenever it switches to open loop it will do that and eventually it will just go back to closed loop and then run fine i bet after you drive for a little bit it will go away. it goes away because your car goes into closed loop, disregards the o2s and run ok, but not perfect.

Louie

replace the o2... its one of the most important parts of your car running worth adamn...