clearing 29E2? HPFP again?

[135mass]

(Sorry for the cross post. Thanks for your consideration. Had no replies on the N54 engine discussion)

Hi folks hoping to get the board's insight on my fact pattern.
2008 135i 125,000 miles bone stock
I had been having recurring limp mode and a variety of misfires. As well as code 29F3 fuel pressure sensor. And then more recently slow rough cold starts and lengthy warm up and "service engine soon" lights. I changed out both the plugs (Bosch OE but not the BMW labeled Bosch) as well as new coils. That seemed to clear the misfire codes. In response to 29F3 I then changed the low pressure fuel sensor out with the improved fuel line and upgraded sensor.

After the fuel pressure sensor fix I am now newly getting code 29E2 which has not previously appeared. That seems to point to another HPFP replacement. The car had the HPFP replaced once approximately 75,000 miles ago. Also 5 of 6 injectors were done but back in 2011.

Using Carly for diagnostics. When I go to clear it the car stalls and also the radiator fan runs wildly as well. Seemed a bit odd to me that 29E2 would only show after the low pressure fuel, sensor was renewed.

Does anyone have any thoughts about clearing 29E2? HPFP again?

Many thanks for your help.

[Mr Gasser]

If you have a fuel pressure gauge, you can hook that up to the fuel lines and check the low pump pressure...sounds like a JB4 richness setting too high, but you say its bone stock...sounds like one of the fuel pumps is going bad, they can still work at low speeds, just crap out when accelerating...If you can figure out where to place the fuel gauge to check and its good, reset the codes and monitor situation...there are two fuel pumps, check the low one...sensors do their job and sense most of the time and replacing them may not be the right way to solve this.

[135mass]

Thanks. Correct I do not have a tune installed. Probably the pump. I will see it Carly can show me the actual fuel pressures. HPFP was replaced but a long time ago. The low pressure pump is original to the car. Do you think the bad Low pressure sensor was somehow masking the code? Now I have constant service engine and constant limp home half engine symbol. Prior to swapping in the low pressure sensor I would get the limp half engine but only on harder acceleration. Thx.

[Mr Gasser]

yes, not sure if the code order makes any logical sense, it should but if the LPFP is still working though not at spec, then the sensor should indicate that its bad and not that the sensor is bad, if that makes any sense...