Hello!
I could really use some help because I am going crazy, I will try to keep this short.
1998 328is Turbo,
Garret gt30 turbo setup (almost identical to TRMS)
* Some reason I decided to build it out myself and literally brought half the stuff from TRM along with my tuning. My exhaust work was done at TRM by someone Michael works with.
The car is currently running on E85 and a stock ecu with the TRM tune for E85.
Car ran great prior to turbo, turbo setup went on and its never been quite right..
What it does:
barely stepping on the gas pedal the car bogs, I can kill the car if I hold it just right.
Drives decently but I can feel soft misses in the 3k rpm range
No check engine light, it comes on prior to start up but then goes out, pull codes with ms41 quick flash, nothing..
What I've done
Compression test, hot test no fuel relay in numbers with 150 +-2 across all 6...
replaced every sensor under the sun with either OEM or recommended by you guys in the forums
All coils and plugs are new, I've tried several gaps with R5671a-7, .018, .022, .025
Pressure tested the entire intake system, pressurized the system prior to the system and checked for leaks, none found.
pressurized the exhaust system to check the manifold, none found.
running a single o2 oem sensor 10"-15" from the turbo, where TRM recommended I place
Wide band shows 14-15, running lean? WOT 13-14.5, had TRM retune it.
Any point in the right direction would be amazing!!!
I keep going back and forth between selling the car and not, I love it but it drives me crazy I cannot solve this issue...
It's weird that out all of that I don't see anywhere where you have said you have checked the fuel system, pressure specifically.
Could be a failing fuel pump or a problem with the pressure regulator whether it be stock or aftermarket.
Easy enough to determine. Then I would suspect the tune. I know some tunes require a resistor in the HFM signal wire and bridging of the 2 ground wires and that those things have caused issues for some.
New doesn't really mean anything, but good that they are
OH one thing I noticed is when I pressured the intake air was coming out of the MAF where the wire harness goes into it. I have a video. Ken at OTP or TRM said they swapped the sensor but it made no difference they said..
I will test fuel pressure at idle and while barely hitting the gas, should I see a flux in the pressure?
I suspect the tune as well but Michael said they built an almost identical car with e85 and had no such issues... same tune..
Fuel pressure goes up 1:1 with boost pressure. Off boost, it will be about 7 psi below base pressure under the vacuum of -20 inch at idle and decrease to 0 boost 0 vacuum as you give it throttle but not enough to spool the turbo to make boost. Base pressure on these cars is 51.5psi. So 44 psi at idle, 51-52 psi at 0 vacuum/boost and 51-52 psi plus boost pressure when in boost.
Ok!
Threw the code 227 mixture deviation bank 1...
Are you tuning it yourself or getting someone else to tune it? I'd personally just give it to a tuner who knows the ECU/software and get them to dyno tune it while working out the kinks.
This has all the sounds of it running lean. Tune, bad fuel pump, injector, big vac leak.
What does your wideband O2 gage say? Hint, hint.
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