Under power and cylinder 5 misfire

[Rob298mx]

It's been close to a year now and we haven't squared away why my car is severely under powered for the given modifications (stage 1 FI TT kit)...it was originally tuned In house with Uprev which made 470 hp at 12psi. On wastegate it made 420 hp, with just exhaust and intake it made 289 hp. So I told myself well maybe I just need to make the jump to EcuTek, maybe the previous tuner was too conservative or maybe he missed something. So I made a phone call to Seb over at Specialty Z and we made the jump to EcuTek and off and running went.

This was strictly a remote tune through Seb. He did a fantastic job keeping up with my log updates and questions, absolutely a stand up guy. We briefly talked about going to flex fuel considering we have corn about an hour away and he was ok with the idea but only after we square away the 93 octane tune. Fair enough. I pre-emtively ordered ID1300s and jammed those in and had Seb tune with those in place. During the logging phases I started to notice a slight skip at idle and there it was, my first cylinder 5 misfire code.

Seb said it could be a bad injector or one that isn't flowing like the others, either way send it back before you toast a cylinder. Done. 650s back in and the car seems to be missing a cylinder.... start my whole diag process, coils, injectors, harness, etc. they all seem to check out. I look at the wideband and the a/f is bouncing between 16-18 so I know there HAS to be a bad injector on that bank, no question. I find that the injectors clips, which are soldered in to be intact, however some of the pins inside the clip seem to be bent. So I bend them out so they make sufficient contact with the injector.

Boom, it works. Logging proceeds forward, T1R calls and says there was nothing wrong with the injectors and they were all within 2% of each other. I tell them I am all set and please return them. I'll just stick with the 650s for now until we get this car figured out. Seb ends the updates at 11psi, asks me how the car feels etc. fantastic, lets hit the rollers and see what she does. Make my way down to the Dyno and she makes 427 first pass at 10psi. mind you the car IAT were in the 130* range...second pass in 4th gear 431...fcuk it lets let the car cool down a bit and revisit. Third pass, 450 at 11psi.

I call up Seb and send him the files, he's completely baffled. He supplies me with a laundry list of stuff to check. So I do, compression test, 220-225 across the board, any loose clamps? Nope. Boost controller hooked up right? Yes according to the greddy Profec manual. In the midst of all this crap I get another cyl 5 misfire code!

So I beg to ask after this lengthy thread, where do I even start?! I ordered a new injector harness, I may do jumper harnesses just to see if it clears the issue. But where am I dropping off almost 100hp?!