Quote:
Originally Posted by tawfeeqh
@ Serial Driver
Note: car runs PI with Fuelit stage 3 LPFP on 100% e85 so in winter long cranks due to fuel vs failing parts bit difficult to work out (for me anyway)
For last couple of months have had long cranks, occasional rough idle in the mornings. On one particular occasion 2 weeks ago I heard misfiring standing behind the car, however got no codes then after 5 mins of driving it went away.
On last Sat morning the half engine light came on as I reversed from the garage with the following codes. I noticed the fan also turning on max but didn't get any waterpump codes:
29E0 - DME Mixture control
29F1- DME Fuel pressure plausibility
2A2B - DME mixture control
2AAE - DME Fuel pump
I don't really have any recent logs except from the last time I headed to the tracks in April this year. In this i noticed the LPFP dipping to 45-50psi on 3rd and 4th gear higher up in the rpm. At the same time the rail pressure dropped closer to 1000psi. However, the AFRs for both banks were stable and the STFTs also stayed within a tolerble range. I got no misfires and zero timing corrections.
Log below:
* http://www.datazap.me/u/tawfeeqh/cal...zoom=2891-3094
I contacted steve at fuelit showing him the logs and he said perhaps its an issue with the wiring. To me it felt like the secondary pump was switching off too early and thats why the rail pressure dropped too. Nizpro tried replicating on the dyno but didn't see the LPFP behaving in the manner it was at the track. I think Steve also mentioned adjusting the hobb switch so they did that. I was totally confused and haven't really investigated much after that. I wasn't getting any codes with the above log too.
This is another log from last year when I ran the 11.1-11.2 sec 1/4 miles. In this the LPFP appears a bit more stable than the April log above. Not sure maybe I need an external fuel regulator.
* http://www.datazap.me/u/tawfeeqh/hea...20&zoom=66-264
My car is not my daily and driven a very minimal amount only on the weekends, so sometimes its weeks until it gets any decent WOT. I thought I would investigate the issues and iron out before the better weather from Sep onwards for the track.
Finally for the three years I have owned the car I haven't really had the common n54 failures apart from the waterpump. I have not changed the HPFP, injectors or coils. I did change the rear o2 sensors last week though. Am running NGK spark plugs with larger gapping and haven't changed in 10,000km.
Well hopefully someone can give some advise on the above.
Any thoughts Coupes33 |
I experience a similar issue (longer cranking time) in winter when initially starting the car cold. I have found pumping the accelerator a bit while cranking gets it going quicker. A long crank for me is around 3-4s. It appears to be a normal issue with running 100% E85.
I looked up those DTCs in the Bentley Service Manual which gives different definitions depending on the different P-Codes for the same BMW FC.
29E0 - P0171 System Too Lean (Bank 1)
- P2188 System Too Rich at idle (Bank 1)
29F1 - P3283 Fuel pressure Control Adaptive Fuel Volume Out of Range (Bank 1)
- P3284 Fuel pressure Control Adaptive Fuel Volume Implausible (Bank 1)
2A2B - P0172 System Too Rich (Bank 1)
2AAE - P1214 Fuel Pumps Feed Too High
- P1215 Fuel Pump Speed Too Low
- P1216 Fuel Pump Emergency Operation
- P1217 Fuel Pump Over Temperature Condition
What does all of that tell you, I am not sure. It certainly appears that something is haywire with the fuel system especially in Bank 1. It could be an injector playing up in Bank 1 or these could be the result of the LPFP being inconsistent. Your latest datalog (April 17) shows the LPFP quickly dropping pressure around 5,800-6,000rpm in each gear. As you stated, it appears that the secondary pump is turning off. A drop in flow from the LPFP would cause the HPFP to struggle and drop pressure at the same time which your log shows. What psi setting do you have your Hobb switch set at? I have the same setup i.e. FueliT Stage 3 LPFP with Hobb switch. Mine is set at 15psi. Your idle issues appear to be fuel related. Maybe too rich fuel fouling spark plugs on start and then they clean up after the engine has run for a while. Maybe get the injectors checked out. I don't know what you can do with the LPFP.