[GhostryJosiah]

Hello all,

Might be a bit of a silly question but I cannot figure out what’s causing my car not to start.

Some context, I have 2012 335is on a MHD OTS stage 2+ E50 tune.

For awhile the car would occasionally not start but after letting it sit for a few hours it would start and run just fine not rough idle, or anything really car runs great. this happened a few times over the last month or 2. Today the car decided to not start so I gave it a few hours, came back and tried again - it did start but then quickly fail on its face.

One odd thing (not sure if it’s related at all) but it only seems to happen when I have about a quarter tank of gas. I check my LPFP and everything looks fine nothing disconnected or out of place and bucket is full.

The codes I am getting are
2AAF
2FDA
2FCA

I want to think it’s the EKP module. But I am not 100% sure ont that. Need some help.

[lookalikehuuh]

You didn't cover this but I assume you have an upgrade Walbro 450 or Walbro 525 fuel pumps correct?

Also is this failure occurring after running the car for a while or does that not matter then stopping the car and trying to turn it back on, or is this occurring on the first start of the day?

[GhostryJosiah]

Originally Posted by lookalikehuuh

You didn't cover this but I assume you have an upgrade Walbro 450 or Walbro 525 fuel pumps correct?

Also is this failure occurring after running the car for a while or does that not matter then stopping the car and trying to turn it back on, or is this occurring on the first start of the day?

I have a 450 that is correct. The failure seems to be if I let the car sit for a period of time. If I drive consistently the issue seems to never happens.

I think it’s the module overheating but I haven’t replaced it because I don’t think is 100% the case, if it was I old expect to fail more and possibly even while driving.

[gbalthrop]

Does your 2012 335is have N54 Engine with MSD80 DME?
Are you SURE the last 2 codes are 2FDA & 2FCA?
BMW Fault Code Lookup does NOT list either of those for MSD80 DME.

INPA or ISTA would display Live Data of LPFP Pressure with Ignition ON, & also allow activation of Pump for test purposes while also showing pressure @ Low Pressure Sensor & @ Fuel Rail (HPFP). INPA will also show Pump Voltage & Amps Draw, which is helpful in diagnosing Pump function.

I am NOT familiar with MHD. Can it show that Live Data? Can it Activate EKPS? Can it show two fuel level sensor values? What are Last-7 Characters of VIN (so we can provide ISTA wiring diagrams)?

You can always "Hotwire" the LPFP, with tank CLOSED so you don't blow yourself up. The Pump could be failing. There could be wiring issues. There could be plumbing issues inside tank. I would suggest Diagnosis BEFORE throwing parts.
George

[marvinstockman]

See if car will start and run for a few seconds on starting fluid.

[itechteam]

What are your psi readings for both low pressure and high pressure fuel pumps? YOu can see that on MHD.

[GhostryJosiah]

Originally Posted by itechteam

What are your psi readings for both low pressure and high pressure fuel pumps? YOu can see that on MHD.

Even when the car can’t start?

[GhostryJosiah]

Originally Posted by gbalthrop

Does your 2012 335is have N54 Engine with MSD80 DME?
Are you SURE the last 2 codes are 2FDA & 2FCA?
BMW Fault Code Lookup does NOT list either of those for MSD80 DME.

INPA or ISTA would display Live Data of LPFP Pressure with Ignition ON, & also allow activation of Pump for test purposes while also showing pressure @ Low Pressure Sensor & @ Fuel Rail (HPFP). INPA will also show Pump Voltage & Amps Draw, which is helpful in diagnosing Pump function.

I am NOT familiar with MHD. Can it show that Live Data? Can it Activate EKPS? Can it show two fuel level sensor values? What are Last-7 Characters of VIN (so we can provide ISTA wiring diagrams)?

You can always "Hotwire" the LPFP, with tank CLOSED so you don't blow yourself up. The Pump could be failing. There could be wiring issues. There could be plumbing issues inside tank. I would suggest Diagnosis BEFORE throwing parts.
George

Might sound dumb, but I don’t have the time to diagnose in-depth. The two parts I assume is cause this aren’t to expensive. I don’t believe it’s my low pressure fuel pump (was recently upgraded a few months back) maybe High pressure but I doubt it.

Car is at 100k so replacing my fuel regulator and the fuel module will hopefully fix it if not no harm parts probably need to replaced at some point anyways.

[GhostryJosiah]

Originally Posted by marvinstockman

See if car will start and run for a few seconds on starting fluid.

I will give this a shot, if it starts I will monitor fuel pressure through MHD to see if anything look abnormal.

[GhostryJosiah]

Happen to have a Fuel Module laying around, forgot I purchased it awhile ago. I replaced it used Protools to code but still no success.

I did notice that I don’t here my pump prime at all. I will open up the tank and take look to see if anything looks weird. Probably remove the pump and see if I can send voltage to it and determine if it operating.

I also ordered a new fuel regulator, because why not? lol. I will do my best to keep the form updated.

[lookalikehuuh]

Originally Posted by GhostryJosiah

Happen to have a Fuel Module laying around, forgot I purchased it awhile ago. I replaced it used Protools to code but still no success.

I did notice that I don’t here my pump prime at all. I will open up the tank and take look to see if anything looks weird. Probably remove the pump and see if I can send voltage to it and determine if it operating.

I also ordered a new fuel regulator, because why not? lol. I will do my best to keep the form updated.

Where did you source your walbro 450 from? They are extremely commonly counterfeit if you don't buy them from a reputable reseller.

Also keep in mind that you WILL LIKELY get fuel pump over current warnings for your car with a Walbro 450. We have found that actively cooling the EKPM will eliminate the overheating of the EKPM, yes even brand new EKPMs will overheat when paired with a Walbro 450.

[GhostryJosiah]

Originally Posted by lookalikehuuh

Where did you source your walbro 450 from? They are extremely commonly counterfeit if you don't buy them from a reputable reseller.

Also keep in mind that you WILL LIKELY get fuel pump over current warnings for your car with a Walbro 450. We have found that actively cooling the EKPM will eliminate the overheating of the EKPM, yes even brand new EKPMs will overheat when paired with a Walbro 450.

Purchase from ECS. I have the precision race works stage 2 bucketed kit.

[GhostryJosiah]

Welp… I think I found the problem.

Not sure how this can happen. Also curious if this could have blown up my car?