johnkk

Feels like a boost leak and most evident in 4th and 5th gear up hills WOT from 3-4k RPM. Car is A6, but posting here since more focus on boost issues. VCDS logs of boost and misfire show no misfires at full boost. No codes. Boost smooth at 3/4 throttle. No mileage issues and idle smooth.

Ran smoke test on vacuum and boost plumbing with no leaks detected. Bypassed N249 with no change. Swapped in known good N75 with no change. Sprayed carb cleaner around injectors at idle with no RPM change. Checked wastegate hoses with mityvac, fine. Wastegate levers move properly.

Wondering if I missed intercooler leak, but haven't put in service position for full inspection. I did drop belly pan and got under car while doing boost test. Hoses were solid and no hissing heard or smoke seen towards intercoolers.

Car has 252k with Dahlback stage I chip since 60k. Vacuum hoses nearly all replaced with silicone as was Y hose at intake and f hose. New MAF couple of years ago.

Any other ideas?

johnkk

No hunches?
Leaning toward intercooler leak that I couldn't hear or see smoke.

Injectors?
Put new fuel filter in a couple of years ago, but maybe?

Flyboy

Try asking over on Quattroworld, this forum is lifeless.