P0171 and P0174 codes after changing Valve Cover Gasket

[bmwdirtracer]

Test fuel pressure too, under heavy load. How old is the fuel filter?

[Majorbimmer]

Update. Took it to the shop today.
After sitting for two days the service engine light was off when I started up the car. It came on when the temp gauge reached the middle (operating temp) halfway to the shop.
Shop ran another smoke test; no leaks were found. Going to have them change the fuel filter as I don't have any records from previous owner that it has been changed.

[Majorbimmer]

Got it back from the shop today.
New fuel filter, air injection valve and Air Distribution Hose. Light was off when I picked it up and a couple miles down the road it came back on again.
Shop said I should have the software updated by the dealer as the next step.

[bmwdirtracer]

I'm sorry to say that "updating the software" isn't really an applicable fix for your car, and your issue. If we were talking about, say, a 2012 335i, then sure...that's a strong possibility. (Just an example). That said, IF your car has original software, well, it's not going to hurt to update it - but I'd bet dimes to dollars that it won't fix it either.

I understand that your shop is madly searching for possible answers...but the basics need to come first. The smoke test was a very wise move. And the fuel filter's certainly not a bad idea. However, nobody's taped a fuel pressure gauge to the windshield and gone for a drive, hard on the throttle through a couple of gears. Do we even have long-term fuel trims yet? Anyone looked at the MAF readings, or the O2 sensor data? I know that you've replaced a bunch of stuff, including the O2 sensors, as I recall... I congratulate you on your dedication. Still, a good BMW tech should really spend an hour or two looking at live data for mixture related items (above), and doing the fuel pressure test I've recommended.

I would, at this point, also highly recommend that you pull all 6 injectors, and send them to RC Injection in California for testing, ultrasonic cleaning, "blueprinting", and retesting. This is the best bargain in the automotive world, about $29 per injector, and will absolutely confirm if injectors are your issue, or will prove they weren't. Remember that if one injector per bank is, say, clogged or dripping, the other two injectors on that bank will go way out in the opposite direction. I have sent dozens of sets of injectors to RC, and have always found massive errors corrected by their services.

[Majorbimmer]

I'm sorry to say that "updating the software" isn't really an applicable fix for your car, and your issue. If we were talking about, say, a 2012 335i, then sure...that's a strong possibility. (Just an example). That said, IF your car has original software, well, it's not going to hurt to update it - but I'd bet dimes to dollars that it won't fix it either.

I understand that your shop is madly searching for possible answers...but the basics need to come first. The smoke test was a very wise move. And the fuel filter's certainly not a bad idea. However, nobody's taped a fuel pressure gauge to the windshield and gone for a drive, hard on the throttle through a couple of gears. Do we even have long-term fuel trims yet? Anyone looked at the MAF readings, or the O2 sensor data? I know that you've replaced a bunch of stuff, including the O2 sensors, as I recall... I congratulate you on your dedication. Still, a good BMW tech should really spend an hour or two looking at live data for mixture related items (above), and doing the fuel pressure test I've recommended.

I would, at this point, also highly recommend that you pull all 6 injectors, and send them to RC Injection in California for testing, ultrasonic cleaning, "blueprinting", and retesting. This is the best bargain in the automotive world, about $29 per injector, and will absolutely confirm if injectors are your issue, or will prove they weren't. Remember that if one injector per bank is, say, clogged or dripping, the other two injectors on that bank will go way out in the opposite direction. I have sent dozens of sets of injectors to RC, and have always found massive errors corrected by their services.

I assume I can get the MAF data via my Foxwell scanner? would it also give me fuel trim data?
The oddity is the car runs great. If you put your foot into the accelerator it picks up speed quickly. It idles smoothly etc. I would have though a lean condition would affect performance.

[Majorbimmer]

I assume I can get the MAF data via my Foxwell scanner? would it also give me fuel trim data?
The oddity is the car runs great. If you put your foot into the accelerator it picks up speed quickly. It idles smoothly etc. I would have though a lean condition would affect performance.

Image is the Air Mass at idle.

20220517_191013.jpg

[shadowpuck]

11.50 kg/h is about 3.2 g/s if google is correct.

that seems in the realm of plausible if the engine is at idle, no accessories.
i'd wait for chris' thoughts on that.

yes, your foxwell will show you fuel trims - both in the bmw side (if equipped) and the obd2 side.

[Majorbimmer]

STFT on bank 1 is 15.60% at idle at 2500 RPM it's all over the place. LTFT stayed at 11.70%

[bmwdirtracer]

The engine computer is adding a bunch of fuel.

Keep in mind that each oxygen sensor reads 3 cylinders. Therefore if, say, injectors 3 and 6 are clogged and delivering only half as much fuel as they should, the DME will see excess oxygen from incomplete combustion and add more fuel to all 3 cylinders on that bank, making two cylinders run too rich while the third is still running lean.

Have a look at the attached report from RC Injection. This is from an E30 RACE CAR! The car "ran fine", but imagine how much more power it would have had if it were receiving the other 60% of fuel it needed on cylinder 3, and the additional 40% on cylinder 5.

[Majorbimmer]

Update:

Took it to another shop. Smoke test found leakage in the valve cover. Seems the aftermarket valve cover warped within 8 months. Replaced it with an OEM one and all has been good since.