Thread: Cold problem?

In the mornings its about 15-20* and I ususally start the car 10 min before i leave, it will start right up and idle pretty normal but with a mis every once in awhile. Heres the real problem, it seems to be low on power and causing the trans to stay in first longer than normal. Also idle rough in gear, but you can restart it and it all be back to normal except for a miss while idling in gear but go's away as soon as you take off. It mainly happens in the morning but has happened a few times after work, any idea what it could be? Im kinda thinking something like a sensor since its fine after being restarted once.

Ive already changed the front and rear oxygen sensors, cardone maf, new plugs and wires. The maf and oxygen sensors seemed to fix it for about a week, but that was before it was this cold. The car really seems to run stronger in the 45-50* afternoon temps. I do have a very small exhaust leak coming from the flex i think, but you really have to listen to hear it. The only code it throws is P0420, Also the injectors are louder than any other car ive had. I ran injectors cleaner with no change. I only run BP 93 octane.

Sorry for the long post, I hope this gives enough info to help solve the problem
Thanks

Does the mis and rough idle only happen when the motor is still cold? Or when it's up to temp?

Engine temp Dosent really seem to affect it, it will be there till its restarted.

I see where you coming from but wouldnt that make it have a lean condition code? Also where I'd the iat sensor on 04+. Is it built into the throttle body?

There was no sensor on the air box or in the piping connecting it, just the maf. I guess it's built in with the maf, idk why I said throttle body earlier.

Also forgot to mention when it does this, it usually surges some too.

I want to suspect it being a MAF issue, as that can play a roll in the transmission shifting and idle issue.

I can't be for sure though, you could alsways try tapping on the MAF when it does this to see if anything changes.

Hmm never heard that before, I'll give it a shot tomorrow.

Yeah sometimes just a couple taps with a screw driver can show if a sensor is bad.

I hope thats it, the MAF is still under warranty since its only about two months old.

Well i started it up this morning and tapped on the MAF, It ran great all day today and my new one should be here tomorrow.
Thanks Fivefingerdeathunch for that trick.