Hi installed giac today, was running great...but only for the first 15 minutes. When i hit the highway I shifted to top gear and started to give her some gas and that car stuttered and my MIL-malfunction indicator light came on. after a little more driving i started to test her to see if there was power loss...didnt seem to be as car seemed to be just as fast and boost was still increased on boost gauge... but then at another point i started to give her gas, this time in 3rd and the car stuttered once...ugh.. Any advice to what the problem may be?

 

it does not stutter constantly only when i stomp on it, if i gradually give her gas shes good... perhaps there is something wrong with my mass air flow?

 

Most likely fouled spark plug. Now that you're running a chip you should probably get a different set of spark plugs. Most people (my self included) run NGK BKR7E spark plugs. ECS has them I think its less than $10 for a set of them. Also make sure to gap em down to .028

 

wow thats its, thats sweet and simple. Thanks!

 

Well, he's not saying that's a definitive fix, but just a suggestion. Remember, you just swapped complete ECUs, so it may take a bit for the newECU to re-adapt itself (it may think that it is still in the old car). I would drive it a little more to see if it clears up before i swapped plugs.