I've been having an issue for some time now. My car went through a slew of upgrades which I thought might address the issue, so I didn't worry about it too much. My car is a 2011 Z4 N54 30k miles, FBO/inlet/outlet, stock turbos. Under full acceleration (say mash the pedal at 2k) the car builds boost and RPM but hesitates like 100 milliseconds for every second, as if you went to 60% throttle momentarily then back to 100%. From 2k to 6k it will do it 4-5 times on the climb. The car doesn't jerk or anything, not that strong. There are no codes. Vacuum lines look like new. The car makes full boost no issues. Runs like a freight train aside from this funky hesitation.
I'm thinking I have a hardware issue. It was doing it on my 93 pump gas tune. Then I did Index 12s, BL coils, 95770 @ 0.028", LPFP Stage 2, fuel lines, 02 pre-cat sensors, and went to flex fuel. Completely new tune, obviously. It does the same exact thing from E10 to E75. Hence my suspicion that it is hardware. Here's a typical log: https://datazap.me/u/fmorelli/july-1-2018-ff-v1?log=0&data=3-20
@NoQuarter suggested I check out the boost solenoids and wastegates. Before I go checking things (and figure out how to test), I thought I'd pop out to the bigger group and see if there is any advice on tests, other ideas, experiences, et cetera.
Thanks, Filippo
I'm thinking I have a hardware issue. It was doing it on my 93 pump gas tune. Then I did Index 12s, BL coils, 95770 @ 0.028", LPFP Stage 2, fuel lines, 02 pre-cat sensors, and went to flex fuel. Completely new tune, obviously. It does the same exact thing from E10 to E75. Hence my suspicion that it is hardware. Here's a typical log: https://datazap.me/u/fmorelli/july-1-2018-ff-v1?log=0&data=3-20
@NoQuarter suggested I check out the boost solenoids and wastegates. Before I go checking things (and figure out how to test), I thought I'd pop out to the bigger group and see if there is any advice on tests, other ideas, experiences, et cetera.
Thanks, Filippo
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