Tuning gurus, what the heck is up with my car...

[DanMpower]

Cliff: Car has been running flawlessly for 2 months on E85, flashed a revision with higher 2nd gear torque targets and the car started idling bad and threw a P0171 lean mixture bank 1 code. Filled with E30 and flashed with OTS E30 MAP, that fixed the idle issue but now it breaks up after 5k, AFR on bank 1 logs shows 19.11 under WOT pulls.

Below is my OTS E30 Stage 2 Map Log
http://www.bootmod3.net/log?id=5e25020fae729b183f09a532

Details:
My car has been on full E85 for the past couple months with no issues, all logs have been healthy. Since I upgraded to wider tires, I notified my tuner if he could increase the torque targets in 2nd gear since it has no trouble putting it down.

He sent me a revision and I flashed it, the car seemed to run normal right after a few test hits. Came home, parked it for the night and the next morning on the way to work the car had a weird idle, the engine felt really rough.

I wasn't too concerned, after work, the car started acting really wonky, idle was really fluctuating, the engine was really rough, then it threw a CEL for the first time. Made it home and pulled the code and it was P0171 (System too lean Bank 1)

I tried contacting my tuner, haven't heard back yet but in the meantime, I switched back over to the BM3 OTS E30 Map, the tank was nearly empty so I filled it up with a pretty close E30 Mix. Immediately the idle issues went away, it idled perfectly smooth again but when I logged a 3rd gear pull it started breaking up badly after 5k RPMs.

Checking my logs for that run, it looks like Bank 1 AFR's are 19.11! I'm no expert but that doesn't sound right under a WOT pull!


Does it look like a bad O2 sensor? Possible a clogged injector? Any ideas fellas? I just find it weird that this happened after flashing the revision and before that the car had been running flawlessly for 2 months. Maybe a coincidence?

[LINF83]

You might want to put it back to pump gas and see how it does

[DanMpower]

Originally Posted by RyF80

You might want to put it back to pump gas and see how it does

Yeah, that's the next step. I gotta find out how to siphon out this tank of E30 now...

On a side note.
Pulled the following codes from BM3 software.

1. 118401 Mixture Too Lean Bank 1
2. 12B104 Lambda Probe Heating Before Catalytic Converter Activation Open Circuit
3. 118001 Mixture Control: fuel-air mixture too lean

Looks like the 2nd code might be pointing to an 02 sensor failure?

[behindthen0thing]

Change that o2 sensor

[DanMpower]

Originally Posted by behindthen0thing

Change that o2 sensor

I have one in my FCPEuro shopping cart, I just wanted a couple of opinions before I drop $300.

[BuLoOoSki]

I would check the spark plugs also, how old are they? Are your running stock spark plugs? And have you gapped them?

[DanMpower]

Spark plugs were changed to NGK 97506 1 step colder plugs in anticipation of running E85. Gapped at .020

This was done 2 months ago and have a total of 1500 miles on them.

Other mods are K&N Drop-In filters, Akrapovic downpipes, and MaxPSI Crank Hub.

[mdma-zn]

Originally Posted by RSXiMUS

Yeah, that's the next step. I gotta find out how to siphon out this tank of E30 now...

On a side note.
Pulled the following codes from BM3 software.

1. 118401 Mixture Too Lean Bank 1
2. 12B104 Lambda Probe Heating Before Catalytic Converter Activation Open Circuit
3. 118001 Mixture Control: fuel-air mixture too lean

Looks like the 2nd code might be pointing to an 02 sensor failure?

Agreed - Cylinders 1-3, O2 sensor before cat
(STFT1 is reading 1 or max; actual AFR's are out)

[behindthen0thing]

Originally Posted by RSXiMUS

I have one in my FCPEuro shopping cart, I just wanted a couple of opinions before I drop $300.

You might be able to find a Bosch o2 sensor that is the same for much cheaper.
I changed my downstream o2 sensor and found a bosch branded one that crossed with the BMW number. It was like 90$ and has been working fine

[DanMpower]

Originally Posted by behindthen0thing

You might be able to find a Bosch o2 sensor that is the same for much cheaper.
I changed my downstream o2 sensor and found a bosch branded one that crossed with the BMW number. It was like 90$ and has been working fine

Unfortunately, I couldn't find a Bosch branded OE sensor for the bank 1 upstream sensor. They do offer a downstream one like you said which is significantly cheaper. Bummer. Thanks for the suggestion though.

[behindthen0thing]

Originally Posted by RSXiMUS

Unfortunately, I couldn't find a Bosch branded OE sensor for the bank 1 upstream sensor. They do offer a downstream one like you said which is significantly cheaper. Bummer. Thanks for the suggestion though.

Sorry it didn't work out.