Some 3rd gear pulls to try and figure out why she's not making power. Shell 93 with 1 gal of GATE E85. APR LT 91 octane tune.
Got annoyed at her. My GTI feels like it's way down in power in the midrange today compared to yesterday and the day before. Not sure why. Filled up with 93 last night at Shell so I figured maybe it's some weak gas and added a gallon of E85. Seemed to help a little bit over 20 miles or so but still feels weak. Not getting that "rubber band" feeling when I roll into full throttle at 2.5-3k RPM and the turbo spools and kicks you back. Not seeing any knock, and it's a 91 octane tune so I wouldn't think a weak batch of 93 would cause much of a noticeable different. Any ideas? It's cold today and IAT's are below 80F while cruising, and down in the low 60s during a pull. Maybe carbon buildup causing inconsistent power? Not the first time this has happened. So strange. Might try to get some logs later tonight after traffic dies down (I have to break in some brake pads anyways).
No codes, noises, or vibrations. Running fine otherwise. Power in the top end over 4k or so seems pretty normal. It's hard to describe -- almost like the turbo wasn't spooling fast and was rolling onto boost a little slower. Hmm. I'll add requested boost to the list of parameters when I log.
I've had this happen before, but it got to normal after a few pulls so I assumed heat soak. But this clearly isn't that.
3rd gear pulls:
- Onset felt weak. Power below 4k was poor. A little better over 4k but still lacking.
- Same
- Same
A few observations: Timing advance is kinda weak at the start and above 4k. Also noticing timing advance at boost onset is a little bit variable. Seems to drop back a degree or 2 at times.
I'm really not sure what to make of it. Unfortunately, none of my PIDs for requested boost work. Does spool seem slow? And the sensor for boost never reads over 22.xx PSI. So good luck with this shit
I would say it’s gas, but a gallon of E should’ve cleared that up. Now’s the time I wish APR had a home-flash tool so I could take the tune off and eliminate that as a variable
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On the bright side, these pulls gave me a good opportunity to bed in the new brakes 🫠
