Chasing P0172 and P0175 System too rich codes

[e39_touring]

That's weird that LTFT and STFT seem to be offsetting each other. What are the #'s for each bank (are both banks behaving the same)? General rule of thumb is that if both banks are the same, it's a general air or fuel delivery problem. If the problem is only showing on 1 bank, then it's more likely coils, injectors, etc.

[Overboost]

Both banks so I am guessing we don't have a catalytic converter clog or a faulty injector. The X5 runs flawlessly at cold start, pulls hard to redline (as much as a 3.0L can ) and never skips a beat. I am wondering about vanos activity, but I don't have the OBD PID for those, but maybe something there? I would think I would have a lazy bottom end or top end if they were acting up...

[andrewwynn]

I checked my fuel trim lay night cold start it was very high so I reset adaptations now I have to wait until I drive the car before the trim will reset. I realized I didn't reset when I swapped my MAF with wife

[Overboost]

Originally Posted by andrewwynn

I checked my fuel trim lay night cold start it was very high so I reset adaptations now I have to wait until I drive the car before the trim will reset. I realized I didn't reset when I swapped my MAF with wife

Let me know what your MAF values are at warm idle with A/C, radio and headlights off. That would help me, thanks.

[andrewwynn]

I will do that. I cheat by having two near identical M54 X5s so I always have a "control". I've been trying to figure out since we bought the cars why wife's gets much better mpg so I swapped the MAF a few months ago after I put new pre cat O2 in my car and no change in mpg. I realized I've never actually MEASURED our consumption and the computer might be calibrated wrong.

I'll get some MAF and fuel trim numbers from both our cars for comparison.

[Overboost]

Originally Posted by andrewwynn

I'll get some MAF and fuel trim numbers from both our cars for comparison.

Thank you brother!

FYI, my average consumption is 17.5 MPG (BMW OBC reporting) for normal city driving

[Overboost]

So maybe the BMW Gods are just having fun with me now...

I had been noticing my cranking was a little slower than normal after sitting a couple of days. I know my battery was going on 4 years old so I replaced it today with a AGM battery. Once I installed it I checked the trims and both banks LTFT were at 0%. Can anyone confirm disconnecting the battery can reset adaptations?

Drove a few miles later and connected my scanner to find this... I haven't seen positive LTFT since I started this journey...

[andrewwynn]

Bat disconnect is the NORMAL way to reset adaptations. :-)


Long and short opposite still is supposed to be maf related.

[andrewwynn]

Follow up on the slow crank: about HALF of the slow crank situations are from a bad starter.

Check your starter current to confirm it's in the normal range so you don't ruin a brand new AGM battery.

If you have a DMM with a peak reading ability (most fluke will do this), there is an easy process you can do. Else newer clamp ammeters can do DC.

I just realized an AC ammeter will give you a reading from a DC pulse so though not an accurate DC reading it should be a relative # that can be compared if you have a control so I'll get an ac ammeter pulse reading.

[Overboost]

Originally Posted by andrewwynn

Follow up on the slow crank: about HALF of the slow crank situations are from a bad starter.

Check your starter current to confirm it's in the normal range so you don't ruin a brand new AGM battery.

If you have a DMM with a peak reading ability (most fluke will do this), there is an easy process you can do. Else newer clamp ammeters can do DC.

I just realized an AC ammeter will give you a reading from a DC pulse so though not an accurate DC reading it should be a relative # that can be compared if you have a control so I'll get an ac ammeter pulse reading.

The battery was old and even though it would have lasted longer, I just PM'd it. Cranking was definitely faster as soon as the AGM was installed and this morning. Cold start log this morning showed 4.6 g/s at the MAF, going to do a warm idle log later today.