So some background.
It's a 1999 GTP with a replacement L67 out of a 2004 Impala SS. The fuel rail that came on it has the circle thing I will post a picture of it circled in blue. The reason I circle that piece in blue is because there is a ticking noise coming from it? Curious as to why it could be ticking?
The engine was regasketed from bottom up and I put a Comp Cam 76-802-9 cam in it with supporting mods including headers. And an MPS with 3.4" pulley.
Got it tuned by a guy relatively local to me. More local to me than anyone else =P
Stock injectors and new stock fuel pump.
The car idles funny, like it can't decide where to properly set the idle rpm's. Idle fuel pressure is 70psi at the fuel rail and it holds that steady. In idle LTFT's are up to +10
The car drives pretty normal, LTFT's go to -22 so I believe it's running quite rich now since my gas mileage used to be about 29 highway on 93 octane but is now about 22 to 22.7 highway on 93 octane =/
Before my recent tune, the car would see up to 7* of knock which was on both the 3.4 and 3.2" pulley. So the knock seems to me to not be boost related. But now I don't really see knock until after 60mph ish.
It seems the injectors run static at around 5500rpm's and then I start knocking slightly. Now, the log that was taken showed that when the injectors hit 18ms which was at around 5.5k rpms, the knock started rising, and at the same time the LTFT's were -12.5. So the car is trying to open the injectors 100%, but pull 12.5% fuel at the same time? Shouldn't it lower the pulse width if it wants to cut back on the fueling slightly?
So it seems the car is commanding more fuel (opening injectors more), then realizing it's running rich it tries to pull fuel (-12.5 LTFT), and it's trying to do both at the same time and is fighting itself? Unless I have this wrong.
MAF is about 10k miles old and has been cleaned in that time once to make sure it wasn't the issue/part of the issue.
Looking for some thoughts/ideas of what the problem could be. And no vacuum leaks, Seafoam test passed, no smoke.
