2012 135i DCT Engine Malfunction Reduced Power

[Liquidsk8s]

Hey guys, first post, naturally it's for an issue haha.

So I've been reading up on the "Engine Malfunction Reduced Power" threads others have made, and mine is a little different/weird.

Car is completely stock, 135i N55 DCT M Sport 56k miles. Spark plugs changed 500 miles ago (few weeks) to stock plugs/gap. Did oil at the same time (oil level is perfect still). Had a few spirited drives here and there but mostly quick trips to the store. I don't drive a lot since I take the train into the city. Nothing has stood out to me. Spark plugs were BOSCH ZR5TPP33S

Fast forward to today. My wife went to the store, then called me because as she backed out of her parking spot the car shuddered and died, giving the Engine Malfunction warning. Restarted and warning was gone and car drove fine. Later she mentioned shes had a few moments where shes had a delay in power recently. She continues on her errands and come home with no further incidents.

Now I'm jumping into it and trying to recreate the issue. Start it up, no issue, idles fine. After 5min of idle it suddenly shudders and shuts off giving the warning. Threw my scanner on and pulled only one code P10D9 for the fuel rail sensor. No CEL on the dash though. Cleared and restarted to see if it would pop up again. Let it idle for 15min with no more issues. Took it out for a drive and car felt more responsive, WOT with zero issue. Parked and went into the store, came out and started the car......shudder and die. Restart shudder but stayed on this time and then idled normal. Revs fine, no codes thrown. Drove home went WOT once and it was perfect with zero issue.

My first thoughts were HPFP, but everything I've seen on those tends to be with the N54, and are not intermittent and only at idle like mine. They also tend to throw multiple codes not just one. Which makes me think I should start with this as the cheapest starting point since the only CEL was aimed at this. Fuel Pressure Sensor

I don't think it's the plugs since the car drives perfect, WOT no issue, no misfire codes etc. I'll keep you posted on what I find, and any thoughts/advice are much appreciated. First BMW and first electrical gremlin lol.

[Gangplank]

Is that a bmw scanner or generic OBDII

[Liquidsk8s]

Originally Posted by Gangplank

Is that a bmw scanner or generic OBDII

Generic OBDII. I ordered an OBDII scanner that I plan to use with MHD tomorrow to run logs and try to pinpoint the issue.

[duder13]

The only thing I can contribute is that my car started intermittently going into limp mode last month, and it turned out to the the water pump and thermostat. If I stopped the car and restarted, the error would go away and things would continue as normal until the next limp mode event. Granted, I was getting the red car-on-a-lift error message when the car would go limp, so I don't know if this is applicable to you.

[Liquidsk8s]

Originally Posted by duder13

The only thing I can contribute is that my car started intermittently going into limp mode last month, and it turned out to the the water pump and thermostat. If I stopped the car and restarted, the error would go away and things would continue as normal until the next limp mode event. Granted, I was getting the red car-on-a-lift error message when the car would go limp, so I don't know if this is applicable to you.

It might be applicable actually. I didn’t get a red car on the lift, but it did happen on the warmest day we’ve had in awhile, 75°. Next day was 45° and no issues.

[Esteban]

Once when my car was running rough and stalled I checked the car with a generic scanner and got codes P0171 and P10D9. Also got a yellow half engine light. Cleared the codes and the car ran fine. A couple weeks later it started running rough/stalled again and this time I checked for codes with Carly and got code 002BDA (rail pressure sensor, electrical: short circuit to ground). My indy shop suggested and replaced the High Pressure Fuel Sensor (P/N 13537620946) and the problem never came back. This was more than a year ago.

[duder13]

With the 135i, when in doubt, check the: charge pipe, OFHG, water pump and HPFP.

Those are pretty much the 4 horseman of the 135i apocalypse. I replaced 3 of the 4 this past year! Just waiting for that HPFP to go so I can seal the deal.

[dtla1]

I agree with Esteban and I think I recommended his exact same procedure in the other thread OP made before they moved it to here.

Clear codes, if it comes back, recheck codes with BMW scanner. Most likely Fuel Pressure Sensor. If that doesn't fix it, might be HPFP. Usually HPFP throws a "Fuel Pressure too Low" or something like that code though.

[Liquidsk8s]

Thanks for the replies guys. Here's an update.

Went a week without issue, did a 3hr drive there and back no issues. Then the other night on my way home it had the issue pop up again. Each time it happens at idle, this time in b2b traffic. Pulled the code, P10D9 again and only that code.

Just ordered a new fuel sensor which arrives tomorrow. I'll keep you updated.

[dtla1]

Originally Posted by Liquidsk8s

Thanks for the replies guys. Here's an update.

Went a week without issue, did a 3hr drive there and back no issues. Then the other night on my way home it had the issue pop up again. Each time it happens at idle, this time in b2b traffic. Pulled the code, P10D9 again and only that code.

Just ordered a new fuel sensor which arrives tomorrow. I'll keep you updated.

Based on this, I think I would def rule out the HPFP. From what I recall on my HPFP failure, it never had issues at idle or low load, it was always a pass on the highway or other high load situation where the car would stutter, throw a code and go into like a semi-limp mode.

[Esteban]

Originally Posted by Liquidsk8s

Thanks for the replies guys. Here's an update.

Went a week without issue, did a 3hr drive there and back no issues. Then the other night on my way home it had the issue pop up again. Each time it happens at idle, this time in b2b traffic. Pulled the code, P10D9 again and only that code.

Just ordered a new fuel sensor which arrives tomorrow. I'll keep you updated.

My shop said based on my symptoms and the code displayed, it could be the HPFP or the High Pressure Fuel Sensor, and since the sensor is cheaper, he suggested to go that route first, and it worked for me. Maybe it'll work for you too.

dtla1, curious, what code did your car display when you had to replace your HPFP?

[dtla1]

Originally Posted by Esteban

My shop said based on my symptoms and the code displayed, it could be the HPFP or the High Pressure Fuel Sensor, and since the sensor is cheaper, he suggested to go that route first, and it worked for me. Maybe it'll work for you too.

dtla1, curious, what code did your car display when you had to replace your HPFP?

Originally Posted by Esteban

My shop said based on my symptoms and the code displayed, it could be the HPFP or the High Pressure Fuel Sensor, and since the sensor is cheaper, he suggested to go that route first, and it worked for me. Maybe it'll work for you too.

dtla1, curious, what code did your car display when you had to replace your HPFP?

Here are the codes