[Nolo24]

Hey all, new to the forums and need some help. I have an 04 325i that's going into limp mode around 4250rpm's, turn it off and back on and it's out of it and will drive like normal. The car sat for about 2-3 years, the previous owner said that they'd had some cooling issue (possibly thermostat) worked on but had issues with the car and never got around to fixing it. Changed the oil and cpv valve, upper and lower intake boots, replaced camshaft pos sensor, added liquimoly lifter additive due to a sticking lifter giving off a knocking noise, fresh gas in it and this is the issue I'm left with. EML as well as TCS lights kick on when limp mode engages, throttle position is largely ignored, just automatic blips of the throttle that the engine gives.

Cleared the codes before putting it into limp mode to try and get the most accurate ones that are relevant.
Under Engine codes:
2F9A - P0070 - Ambient Air Temp Sensor
279C - P0599 - Thermostat heater control Circuit high
28A2 - P16A7 - Control Module Self-Test, hot film air mass meter monitor
The first two popped back up immediately after restarting post code clear, the third only appeared after limp mode was engaged.

Transmission:
145 - Can engine intervention (only after limp mode engaged.)
(Before clearing, 145, 146, 96, and 113 were present.)

ABS:
5E19 - data error from engine ecu (only after limp mode.)

Any and all help would be appreciated. I've checked out quite a few forums but none of the ones I saw were exactly the same as what I'm after. (edited to add code meanings)

 

[BaliDawg]

Go look up each code description on bmwfault.codes, or get them from your scan tool/software, and add after each code above.
Otherwise, EVERYONE who wants to help you has to go look them up.

 

[Nolo24]

Go look up each code description on bmwfault.codes, or get them from your scan tool/software, and add after each code above.
Otherwise, EVERYONE who wants to help you has to go look them up.

Tried to add both any details I could get on them, i do have INPA but the last third of my copy is in german so I'm a bit limited in that regard

 

[BaliDawg]

Ok great, next step is to search for each of those error codes to see what they indicate.

From experience, I can say the air temp sensor and thermostat codes are important, but not critical. The EGS (transmission) and DSC codes are a side effect of a DME malfunction. The 28A2 DME code is the serious one to focus on since it is causing engine limp mode. I found 28A2 (P16A7) Air path: monitoring, which is related to the MAF sensor.

P16a7 - Engine Control Module Self-Test Mass Air Flow Sensor Monitoring Fault

The Engine Control Module (ECM) monitors the Engine Control Module Self-Test Mass Air Flow Sensor Monitoring. The ECM sets the OBDII code when the Engine

www.engine-codes.com

Check its wiring from the connector to the DME plugs.
What is the MAF value at hot idle in grams/second units? It should be around 3.0-3.2 g/s.