RaggedEdge wrote:
For anyone reading this, I've been blindly trying to figure this out, and loaded the Performance 91 tune back on. As I stated before on stock tune it stays at a rock steady 10 PSI, which I read to be normal on the stock tune. However today, when running on the 91 canned tune, in full boost, it's fluctuating between approximately 14.5 PSI and 17.5 PSI. I would have data logged it but I accidentally left my laptop at work so I'll have to do it Monday...
The only reason it would do this is an improperly adjusted wastegate as the pcm is trying to achieve 17.5 psi. When you started this thread it was about a misifire and part throttle which made it look like you had an old tune which did this at certain times. Now it comes out that its the boost fluctuating. These are two different issues an when not clear about what's going on it's hard to resolve your issue.
So from what I can gather I'd have to assume that your misfire issue was fixed with the plugs and gap as it should have been which is why those plugs are recommended.
Now all you need to do is adjust the wastegate and it should be good.
The last tune you posted still says it was modified. What are the modfications you made to it?