I had a mild case of this same problem. Changed plugs and MAP sensor, didn't help. Took it in for injector cleaning and it worked like a charm. Make sure they do the throttle body, too. Shouldn't cost more than $50-60.

 

who can do all this for that much? The dealerships?

 

We charge $165.00 for induction service and $165.00 for throttle body cleaning. Not sure where the $50-60 price is coming from.

 

I wonder if weather effects the map sensor,mine started right as it began to get cold. because I just went through the same problem. Luckily mine only needed the ole map sensor whack. Our throttle bodies to tend to get dirty rather quick. also check vafc settings and connections. when i first installed mine i had a loose wire that gave me big problems similar to yours.

 

Do it yourself man I did it myself the fluid I was talking about is topend cleaner, when I get home ill snap some pix. It's pretty easy. You just need a bottle that feeds the fluid kinda slow and hold your rpms at 1800 it'll take 15-20mins you just connect it to manifold vaccum. Than get some fuel injector cleaner for your gas tank. Buy yourself some throttle body cleaner. Whole thing should only take like 45mins.