[Spooly]

My car cranked slightly longer than normal last week, but then started up and ran fine. I checked fuel rail pressure and it was perfect.
However, after parking for 10 mins and trying to start it up again, it started rough and threw a half-CEL. Codes thrown are:

• 2BDA "Rail pressure sensor, electrical: Short circuit to ground."
  and shadow codes for
• 2BDE (Shadow code) "Fuel high pressure on enabling of injection: pressure too low"
• 2BF0 (Shadow code, translated from German) "Fuel high pressure at or after injection release 2. environmental condition set after delay pressure too low"

I was wondering if anyone has experienced a similar problem and what the solution might be. I don't think its the sensor/HPFP, if I reset codes the sensor reads fine and pressure looks good. From what I have been able to find online it seems like it might be the fuel pressure regulator or the LPFP? Wish we had a low pressure fuel sensor

[Spooly]

Ended up being the wiring for the sensor, it was incorrectly routed and barely touching the charge pipe. After running the charge pipe would heat soak and the wiring would get hot, messing up the values reported to the DME, causing the short-circuit to ground code for the sensor.

[gbalthrop]

Originally Posted by Spooly

... Wish we had a low pressure fuel sensor

ISTA says 2011 N55 DOES have Low Pressure Sensor (B6125a in attached ScreenPrint). Please advise if yours does NOT.
You don't say what Scan Tool or Diagnostic Software you are using, but it SHOULD show BOTH Rail Pressure (HPFP) AND
LP Sensor values (LPFP).
George

[Spooly]

Originally Posted by gbalthrop

ISTA says 2011 N55 DOES have Low Pressure Sensor (B6125a in attached ScreenPrint). Please advise if yours does NOT.
You don't say what Scan Tool or Diagnostic Software you are using, but it SHOULD show BOTH Rail Pressure (HPFP) AND
LP Sensor values (LPFP).
George

That's interesting, it's not available in MHD and when I looked I didn't see it. I wonder if ISTA is wrong, that'd be surprising.
https://www.e90post.com/forums/showthread.php?t=1504469

[gbalthrop]

Originally Posted by Spooly

That's interesting, it's not available in MHD and when I looked I didn't see it. I wonder if ISTA is wrong, that'd be surprising.
https://www.e90post.com/forums/showthread.php?t=1504469

I don't know anything about the history of the N55 engine. My recollection is that it was used in other countries/ markets BEFORE it became available in US. ISTA DOES show things in wiring diagrams that are NOT used in US market in some models, such as Water Valve and Auxiliary Pump in N52/328i/xi diagrams.

I notice the SSP # in the ScreenPrint I attached is EARLIER than the 2010 N54 SSP # for 1/2010 N54 E90. I do know that N54 owners have reported reading BOTH LOW Pressure value and High Pressure (Rail) Value. First post in 6/09/2018 thread you linked shows pressure port for B6125a Sensor blanked off & NO Sensor Connector (x63280). Cost-Saving on US N55??
George