Could a dirty TB cause a high cold start idle?
 

Does anybody know if a dirty throttle body could cause a high cold start idle? My car is revving up to 2100-2200rpm on cold starts, and I can see from my tuner that the desired idle is only about ~1500rpm. I've contact Doug at Bamachips and he's sent me new tunes that were supposed to fix the problem but it hasn't made a difference. Seems that every time I reflash the PCM, it goes away for a few days but then comes back again.

Not sure what would cause it... but i live in minnesota, and really cold days mine will idle closer to 2000 than 1500 for a few minutes before it idles down, i don't have too many mods done yet... so i'm thinkin maybe thats just normal

This is not normal, it started happeneing after I switched over from a Diablosport tuner to a SCT tuner. I ordered a new tune from Bamachips.

During cold starts, mine goes to 2k, and then comes down to about 1300. After a couple of minutes, it goes to normal idle.

I use a race tune from Bama and mine does the same thing.

Revving up to 2k or so and slowling dropping to 1k and then 750 for me is perfectly normal. Your car stays at 1500rpm? If it's really cold here (30's), then it takes for ever for mine to idle normally.

I don't understand why it NEVER did this when I was running my Diablosport tuner.

there are tables for startup idle that are relative to temp and time. these tables also have adders for different specifics. If it didnt do it with your Diablo then the person that made the diablo tune removed them. The car should startup around 1800-2k for a second then fall to the low to mid teens then to base idle after a specified time/temp. These can be removed and I'm sure Bama would do this for you but not sure why you would want to?

but to answer your question a dirty tb could definately effect the idle but you would notice it all the time. Coking buildup on a throttle plate typically causes a slight miss sound at an idle and sometimes causes a "sticky throttle" feel and a hesitation

2100+rpm on cold starts?