Lately, when I start my car it stumbles at about 200-300 rpm, then will go up. Occasionally it will shut off completely then start right up the 2nd time. I am also getting very poor gas mileage, and when hooked up to a scanner, I am getting about 15* of knock when the throttle is about 3/4 of the way down. Thanks for any input that you can give me.

 

doubt it because they only work in closed loop try cleaning the IAC

 

How's your fuel pressure? Could be your fuel pump going out....

As far as the O2s causing it to stall upon start up, as predator pointed out, it's not likely. The reason is, the O2s readings not being used by the PCM for fuel calculations until the coolant reaches a certain temp.

Thomas.

 

Thanks guys. Would the o2 sensors be a possiblity in causing my 15*'s of knock?

 

how long since your changed your fuel filter?

 

Hasn't been replaced in a little over a year

 

My car is having pretty close to the same problem but I don't get any knock, start and die, try again, give it a little gas and she's ok.

I'm pretty much decided that it's either my ignition or iac because the car runs great every time after a minute or two.