Engine stumble around 2.5k rpm in cold weather
 

Hi all,

Just wondering if anyone has had this issue and how they fixed/had it fixed? I always let my car do its little loud cold idle thing on start ups, but now that it's cold, even after this, I get some stumbling around 2500 rpm and light throttle. I don't shift past 3-3.5k rpm or mash the throttle until the water is at operating temp. It only does this when it's cold weather outside.

My logic tells me that until it's warm, the car runs a little richer than normal and that's where the stumble comes from, but not sure.

Mods: Borla UEL header and catback, K&N drop in air filter.

Well, I haven't noticed that aberration ..... but it hasn't gotten below freezing here, yet. Do you park outside or in a garage?

I'd suggest not only waiting for the engine to do its little warm up dance (20-25 seconds), but wait another minute or so before moving off. The extra time just may be what the cat needs to warm up a bit more and tell the ECU to "carry on".

humfrz - guessing again .....;)

If I were you, I would swap out the k&n with oem filter, reset ecu and see if that problem still there.