[mecheng77]

Went to start my car, it cranks healthy but no start. It has no codes, the codes it shows are non related. Any idea?

[mecheng77]

I watched a bunch of youtube videos on the problem. Some point to a bad fuel pump relay. I first checked the fuel pump fuse, it was okay. After I checked it, I decided to try to start the car. When it turned over, I felt it had some life, after a couple of tries I remember a video that said to hold down the accelerator which I did and it finally came to life and smoked for a couple of seconds but is runny fine.

This is really bizarre but maybe disconnecting the fuel pump fuse unstuck the fuel pump relay? I checked the two relays under the hood and they seem to click fine with a 9V battery but maybe I will change them. There is two relays with the same partnumber, both Tyco blue, not sure which one is the fuel pump relay? Has anyone else had them fail or maybe the car was flooded, which is odd.

[ctuna]

If you have an N51 engine the Hoses in the Tank are noted
to disassemble.
That will give you no codes and no fuel pressure.

If you have the N51 engine the Fuel Tank Hoses self disconnecting
,internal to the tank.
is a known problem even happened on there last model .
Effects all SULEV models. There solution is to replace the whole
tank at your expense. Every once in awhile we get somebody coming
here with this problem.
Supposedly BMW is suppose to cover this under the SULEV Warranty
but this may vary by state and dealership.
I would talk to BMW about the warranty .
Don't ever take a BMW to a dealership if you are out of warranty.
By the way there are not two fuel tanks there are two fuel lines
to either side of the tank though.

Yeah the fuel pump is inside the tank but the fuel lines disconnecting is the problem
for the N51.(inside the tank)
Fuel pump is inside the tank on the other car's to but that does not mean its unreachable
in either case.

https://www.e90post.com/forums/showthread.php?t=1063062

[mecheng77]

Originally Posted by ctuna

If you have an N51 engine the Hoses in the Tank are noted
to disassemble.
That will give you no codes and no fuel pressure.

If you have the N51 engine the Fuel Tank Hoses self disconnecting
,internal to the tank.
is a known problem even happened on there last model .
Effects all SULEV models. There solution is to replace the whole
tank at your expense. Every once in awhile we get somebody coming
here with this problem.
Supposedly BMW is suppose to cover this under the SULEV Warranty
but this may vary by state and dealership.
I would talk to BMW about the warranty .
Don't ever take a BMW to a dealership if you are out of warranty.
By the way there are not two fuel tanks there are two fuel lines
to either side of the tank though.

Yeah the fuel pump is inside the tank but the fuel lines disconnecting is the problem
for the N51.(inside the tank)
Fuel pump is inside the tank on the other car's to but that does not mean its unreachable
in either case.

https://www.e90post.com/forums/showthread.php?t=1063062

Originally Posted by ctuna

If you have an N51 engine the Hoses in the Tank are noted
to disassemble.
That will give you no codes and no fuel pressure.

If you have the N51 engine the Fuel Tank Hoses self disconnecting
,internal to the tank.
is a known problem even happened on there last model .
Effects all SULEV models. There solution is to replace the whole
tank at your expense. Every once in awhile we get somebody coming
here with this problem.
Supposedly BMW is suppose to cover this under the SULEV Warranty
but this may vary by state and dealership.
I would talk to BMW about the warranty .
Don't ever take a BMW to a dealership if you are out of warranty.
By the way there are not two fuel tanks there are two fuel lines
to either side of the tank though.

Yeah the fuel pump is inside the tank but the fuel lines disconnecting is the problem
for the N51.(inside the tank)
Fuel pump is inside the tank on the other car's to but that does not mean its unreachable
in either case.

https://www.e90post.com/forums/showthread.php?t=1063062

I have a n52, I think the first time when it didn't start I don't remember the fuel pump priming when I opened the car door. The next time after I checked the fuse I remember the fuel pump priming. Not sure what would cause it to intermittently prime

[gbalthrop]

Originally Posted by mecheng77

I watched a bunch of youtube videos on the problem. Some point to a bad fuel pump relay. [NOT on your N52] I first checked the fuel pump fuse, it was okay. After I checked it, I decided to try to start the car. When it turned over, I felt it had some life, after a couple of tries I remember a video that said to hold down the accelerator which I did and it finally came to life and smoked for a couple of seconds but is runny fine. This is really bizarre but maybe disconnecting the fuel pump fuse unstuck the fuel pump relay? I checked the two relays under the hood and they seem to click fine with a 9V battery but maybe I will change them.

Originally Posted by mecheng77

I have a n52...

AFAIK, NO 2007 328i had a "Fuel Pump Relay", as the EKP Fuel Pump Module (located behind the RR seat squab (backrest) functions as the Relay, as signaled by the DME. There were changes in the electrical circuitry, fuse layout & designations, effective 3/1/2007 in the middle of the 2007 model run, so need to know what your build month/year is. Relay(s) in the E-box under the hood can be K6319 (VVT/Valvetronic Relay) AND, depending upon build date, DME Relay (K6300) & Fuel Injection Relay (K6327), those being for EARLY 2007 models, with relays in the E-box.

Fuse for EKP Module is F88 for LATE 2007 models, and F40 for EARLY 2007 Model.

I would suggest monitoring EKP F5 Status using INPA to determine what is going on with fuel pump operation, voltage, RPM, etc. and/or use F6 Activation to run the pump at 50% of max speed, and watch ACTUAL speed to see if it matches "Setspeed" or commanded/ Activated speed.

Please let us know what you find,
George

[mecheng77]

Originally Posted by gbalthrop

AFAIK, NO 2007 328i had a "Fuel Pump Relay", as the EKP Fuel Pump Module (located behind the RR seat squab (backrest) functions as the Relay, as signaled by the DME. There were changes in the electrical circuitry, fuse layout & designations, effective 3/1/2007 in the middle of the 2007 model run, so need to know what your build month/year is. Relay(s) in the E-box under the hood can be K6319 (VVT/Valvetronic Relay) AND, depending upon build date, DME Relay (K6300) & Fuel Injection Relay (K6327), those being for EARLY 2007 models, with relays in the E-box.

Fuse for EKP Module is F88 for LATE 2007 models, and F40 for EARLY 2007 Model.

I would suggest monitoring EKP F5 Status using INPA to determine what is going on with fuel pump operation, voltage, RPM, etc. and/or use F6 Activation to run the pump at 50% of max speed, and watch ACTUAL speed to see if it matches "Setspeed" or commanded/ Activated speed.

Please let us know what you find,
George

Originally Posted by gbalthrop

AFAIK, NO 2007 328i had a "Fuel Pump Relay", as the EKP Fuel Pump Module (located behind the RR seat squab (backrest) functions as the Relay, as signaled by the DME. There were changes in the electrical circuitry, fuse layout & designations, effective 3/1/2007 in the middle of the 2007 model run, so need to know what your build month/year is. Relay(s) in the E-box under the hood can be K6319 (VVT/Valvetronic Relay) AND, depending upon build date, DME Relay (K6300) & Fuel Injection Relay (K6327), those being for EARLY 2007 models, with relays in the E-box.

Fuse for EKP Module is F88 for LATE 2007 models, and F40 for EARLY 2007 Model.

I would suggest monitoring EKP F5 Status using INPA to determine what is going on with fuel pump operation, voltage, RPM, etc. and/or use F6 Activation to run the pump at 50% of max speed, and watch ACTUAL speed to see if it matches "Setspeed" or commanded/ Activated speed.

Please let us know what you find,
George

Hi George, my build is 2/2007, I can't find a fuel pump relay in RealOEM. It shows two valvtronic relays which seem odd, a fuel injector relay and PCV heater which are all blue and it points to the same location. Is there a way to determine based on wire colour?

https://www.realoem.com/bmw/enUS/par...i&mg=61#36

It's funny you mention the EKP because one video I watched showed a guy with a N54 have the exact same problem and he cured it by changing the module to a newer version which was quite different.

Nothing worst than an intermittent problem. It might never happen again but i want to change some parts if I can prevent it. I'm really surprised BMWs sophisticated electronics do not pull a fault code

[mecheng77]

Update I activated EKP in INPA and it went to 99.4% so that seems fine

[dpaul]

FWIW, A10A is "EWS4 timing challenge / response error".

This conceivably could have something to do with your crank but failure to start, as EWS handshake failure would result in that behavior. However, I'd expect to see a corresponding DME fault which you do not observe. So a plausible guess is that A10A sets when the engine cranks too long without starting.

Now that the engine is running, do you still see A10A in the CAS?

[mecheng77]

Originally Posted by dpaul

FWIW, A10A is "EWS4 timing challenge / response error".

This conceivably could have something to do with your crank but failure to start, as EWS handshake failure would result in that behavior. However, I'd expect to see a corresponding DME fault which you do not observe. So a plausible guess is that A10A sets when the engine cranks too long without starting.

Now that the engine is running, do you still see A10A in the CAS?

Originally Posted by dpaul

FWIW, A10A is "EWS4 timing challenge / response error".

This conceivably could have something to do with your crank but failure to start, as EWS handshake failure would result in that behavior. However, I'd expect to see a corresponding DME fault which you do not observe. So a plausible guess is that A10A sets when the engine cranks too long without starting.

Now that the engine is running, do you still see A10A in the CAS?

Thanks I will check when I'm back home. What would be the fix for that?

[mecheng77]

Started car no issues, scanned for codes and there was none. I ordered two of the blue relays, going to replace them and go from there. Maybe the car flooded, I dunno