Hey guys, about to slam my head into a wall so figured I'd come and poll the audience for input. Life is busy these days and don't have a full weekend to troubleshoot so looking for potential ideas ya'll can think of.
Backgound:
- 2013 Ford Taurus SHO, 72k miles
- XDI-35 hpfp w E30 tune, EPP hot pipes w/ stock BPVs, Gearhead intercooler, BBK throttle body, Airaid Intake, Stainless Works Downpipes, stock catback
Car has been tuned since 22k miles. About 5k miles ago I popped a CEL for a large EVAP leak. Decided to datalog and found that my fuel trims were 1.09 at idle, 1.14 cruising, and 1.32 (yea) at wot and I was now only seeing 12-15 psi instead of the 18 I was getting previously. Used IDS to cycle the purge valve and found it to be bad. Replaced it, no more light but the fuel trims and boost issues remained.
Did a pressure/smoke test and found a few leaking couplers and also found a crack in the oem throttle body so replaced it. Fuel trims dropped to 1.06 at idle, 1.09 cruising, and 1.24 wot. This week I replaced the front and rear pcv valves after finding the rear one to be bad, and as of today (cleared KAM yesterday morning) this is my data:
stft idle - 1.00
stft cruise - 1.06
stft wot - 0.94-0.98
ltft cruise - 1.00
ltft wot - 1.13
commanding 0.81 lambda, seeing 0.87-0.81 wot
hpfp 17.57 mpa (2550 psi)
wastegates are at 95%, were in the 60s before
commanding 232 kpa, only seeing 200 kpa
I replaced the spark plugs last week just to check, but it appears that I have a pretty big leak that can't seem to be found with smoke or positive pressure.
And before anyone mentions the tune, we've tuned this setup many times with great luck, so the chances that our tune is messed up isn't likely.
Last log before I popped the CEL had wastegates around 60% and boost was only about 5 kpa off commanded with near perfect fuel trims.
I was tossing ideas back and forth with a friend that's an ASE tech, and he suggested possibly needing to replace the boost solenoid, but I wasn't really seeing any issues similar to this when checking.
I scoped the impellers when I installed the downpipes and hot pipes and didn't notice any damage or play in the shaft or vanes.
Thoughts? Car is no slouch, it still runs 12.42 @ 110 consistently but feel it should have a lot more in it.