[BimmerMan2421]

Hi all, I am looking to see if anyone has had this no start issue my car is having occur once every blue moon and recently occurred again last week. This is my sister's car so on the occasions the car doesn't start, it is usually when she is driving it so this is based on what she tells me and what I see through FaceTime. What happens is sometimes her car will not start at all, however the engine just cranks and cranks, but it's like there is no fuel being sent to create spark to start the engine. However, on the occasions where I've told her to wait and try starting again say like (typically 10-30 minutes later), the car will start and run perfectly fine; and the car will continue to start perfectly fine and run fine for months. So this issue has been extremely sporadic.

I was thinking that there would be a code stored for the EKP but when I ran the codes with INPA, the codes that popped up were completely unrelated and the EKP module said OK. Also checked Fuse 70 for the fuel pump and the Fuse looked Ok. So now I'm lost. I know I'm getting pressure and that the fuel pump is working because 1) I can hear the pump/car humming whenever I unlock or open a door of the car and 2) the car is currently running and starting perfectly normal for the past 4 days. (Although there was a long crank earlier today for some odd reason but it still started nonetheless).

Sorry for such a long post, but does anyone have any idea what is going on or have had experience with this? I am thinking it has to do with some module or relay that may be going out to cause this issue sporadically.

[Jesda]

Hopefully someone has a more specific answer, but I've owned cars where the crank position sensor will fail slowly in a way that doesn't always throw codes, behaving exactly like this.

[tgeho_e92]

Originally Posted by Jesda

Hopefully someone has a more specific answer, but I've owned cars where the crank position sensor will fail slowly in a way that doesn't always throw codes, behaving exactly like this.

I'm having this same issue with my car sometimes it's "sluggish" to start but it always does haven't had the issue where it wouldn't. I'm going to watch this thread closely.

[marvinstockman]

First, maybe you should trade cars with your sister, so you can troubleshoot the problem when it happens.

Second, when it won't start, see if it will start and run for a few seconds on starter fluid.

[BimmerMan2421]

Originally Posted by marvinstockman

First, maybe you should trade cars with your sister, so you can troubleshoot the problem when it happens.

Second, when it won't start, see if it will start and run for a few seconds on starter fluid.

Yeah I am currently driving her car for the moment to monitor how the car starts and runs. How do I use starter fluid to start the car? Would I have to open the intake?

Originally Posted by Jesda

Hopefully someone has a more specific answer, but I've owned cars where the crank position sensor will fail slowly in a way that doesn't always throw codes, behaving exactly like this.

I hope this isn't the case since I replaced the Crank Position sensor 2 years ago at 97k miles which was a total PIA. However, I remember when the CP sensor failed, the car would start but it would idle extremely sluggish. None of which is currently happening but I hope this isn't the case of a failing CP sensor. Car currently has just under 111k miles.

[ctuna]

N51 have a problem with the Fuel Tank Hoses self disconnecting.
Do a fuel pressure test.

https://www.bimmerfest.com/threads/3...#post-11517585

https://mechanics.stackexchange.com/...but-wont-start

There is no sensor for low fuel pressure on an N51 or N52 I believe.
So it won't throw any codes.

[BimmerMan2421]

Originally Posted by ctuna

N51 have a problem with the Fuel Tank Hoses self disconnecting.
Do a fuel pressure test.

https://www.bimmerfest.com/threads/3...#post-11517585

https://mechanics.stackexchange.com/...but-wont-start

There is no sensor for low fuel pressure on an N51 or N52 I believe.
So it won't throw any codes.

Yeah I have seen a few threads about the Fuel tank hoses being disconnected due to a poorly designed clip. However, those cars were not starting at all, my vehicle is still starting and I have been driving the car for the past week now with no issues. It is only the (now 3) instances where randomly the car would just crank and crank but not start, and then 10-30 mins of waiting later, the car starts and runs fine for the next few months.

I'll definitely look at the threads you linked to see if I can run some tests on the EKP.

Also, I have been receiving Low Battery Charge messages sometimes on the iDrive, could the battery having a low charge be a reason to not send power to the fuel pump or EKP module sometimes?

[dpaul]

Originally Posted by BimmerMan2421

Hi all, I am looking to see if anyone has had this no start issue my car is having occur once every blue moon and recently occurred again last week. This is my sister's car so on the occasions the car doesn't start, it is usually when she is driving it so this is based on what she tells me and what I see through FaceTime. What happens is sometimes her car will not start at all, however the engine just cranks and cranks, but it's like there is no fuel being sent to create spark to start the engine. However, on the occasions where I've told her to wait and try starting again say like (typically 10-30 minutes later), the car will start and run perfectly fine; and the car will continue to start perfectly fine and run fine for months. So this issue has been extremely sporadic.

I was thinking that there would be a code stored for the EKP but when I ran the codes with INPA, the codes that popped up were completely unrelated and the EKP module said OK. Also checked Fuse 70 for the fuel pump and the Fuse looked Ok. So now I'm lost. I know I'm getting pressure and that the fuel pump is working because 1) I can hear the pump/car humming whenever I unlock or open a door of the car and 2) the car is currently running and starting perfectly normal for the past 4 days. (Although there was a long crank earlier today for some odd reason but it still started nonetheless).

Sorry for such a long post, but does anyone have any idea what is going on or have had experience with this? I am thinking it has to do with some module or relay that may be going out to cause this issue sporadically.

You should list all the codes you found, regardless of your opinion about their relevance. Possibly someone else could make a connection between some of those codes and your starting issue.

[gbalthrop]

Originally Posted by BimmerMan2421

... What happens is sometimes her car will not start at all, however the engine just cranks and cranks... on the occasions where I've told her to wait and try starting again say like (typically 10-30 minutes later), the car will start and run perfectly fine; and the car will continue to start perfectly fine and run fine for months... when I ran the codes with INPA, the codes that popped up were completely unrelated and the EKP module said OK...

INPA is a very helpful Diagnostic Software Program. Hope you have gotten past Functional Jobs, which just provides fault codes (in all modules), but NO Definitions, Freeze Frame Data, Details or Fault History. Do I understand correctly that you have read fault codes in the DME (Engine Control Module) after a "Crank, NO Start" issue and there were NO FAULT CODES?

Even if someone had cleared Fault Codes in the DME or EKPS (Fuel Pump Module), each of those Modules has "History Memory" where the last ten fault codes are saved along with some Freeze Frame Data (Snapshot of system conditions at moment Fault was saved, along with Odometer reading in km).

So I would suggest viewing the following screens in INPA, and saving any screens showing fault details:

1) INPA > DME (MSV80) > F4 > F1 > F3 Read Fault Memory with Freeze Frame Data

2) INPA > DME > F4 > F3 > F1 Read History Memory

3) INPA > EKPS > F4 > F1 Read Fault Memory

4) INPA > EKPS > F4 > F5 Read History Memory

If you are NOT sure how to save ScreenPrints of ISTA Screens as JPG image files which you can attach here, see the attached pdf, "INPA Tutorial Quickstart".

George

[marvinstockman]

Regarding the starting fluid, I'd open the air box, remove the air filter, and give a short spray. Then jump in and start the car. Sometimes as fuel pumps wear out their brushes, you get intermittent running, because of poor electrical contact.

[marvinstockman]

With this article as reference, you could also give the fuel pump a wack with a rubber mallet.

https://www.pelicanparts.com/BMW/tec...eplacement.htm

[dpaul]

The assumption that this issue is fuel pump-related seems unwarranted at this point. By the description given, ('cranks but doesn't start') the problem could easily in ignition circuitry or perhaps a transient EWS fault.

Of course, no matter what it is, it would be very surprising if it did not leave code(s).

So list the codes you found. Add CAS to the list of modules you might want to query besides DME and EKPS using the INPA commands suggested by gbalthrop

[BimmerMan2421]

Originally Posted by dpaul

You should list all the codes you found, regardless of your opinion about their relevance. Possibly someone else could make a connection between some of those codes and your starting issue.

I'll post a picture of the error codes that were stored when I plugged in INPA. The rest of the modules all said OKAY.

Originally Posted by gbalthrop

INPA is a very helpful Diagnostic Software Program. Hope you have gotten past Functional Jobs, which just provides fault codes (in all modules), but NO Definitions, Freeze Frame Data, Details or Fault History. Do I understand correctly that you have read fault codes in the DME (Engine Control Module) after a "Crank, NO Start" issue and there were NO FAULT CODES?

Even if someone had cleared Fault Codes in the DME or EKPS (Fuel Pump Module), each of those Modules has "History Memory" where the last ten fault codes are saved along with some Freeze Frame Data (Snapshot of system conditions at moment Fault was saved, along with Odometer reading in km).

So I would suggest viewing the following screens in INPA, and saving any screens showing fault details:

1) INPA > DME (MSV80) > F4 > F1 > F3 Read Fault Memory with Freeze Frame Data

2) INPA > DME > F4 > F3 > F1 Read History Memory

3) INPA > EKPS > F4 > F1 Read Fault Memory

4) INPA > EKPS > F4 > F5 Read History Memory

If you are NOT sure how to save ScreenPrints of ISTA Screens as JPG image files which you can attach here, see the attached pdf, "INPA Tutorial Quickstart".

George

That is what I am super confused about, I was certain that there would be a fault memory stored because when my sister FaceTimed me I saw the check engine light was on while she was trying to start the car. However, when I checked the error memory in INPA the DME and EKP modules said Okay and thats where I was very surprised.

I will definitely check out the other functions for reading the memory when I get the chance though. I usually just stick to read error memory in INPA and not the other F key functions.

Originally Posted by dpaul

The assumption that this issue is fuel pump-related seems unwarranted at this point. By the description given, ('cranks but doesn't start') the problem could easily in ignition circuitry or perhaps a transient EWS fault.

Of course, no matter what it is, it would be very surprising if it did not leave code(s).

So list the codes you found. Add CAS to the list of modules you might want to query besides DME and EKPS using the INPA commands suggested by gbalthrop

Hmmm this is a good point. I just assumed it was fuel pump-related because it seemed like car wasn't receiving gas to ignite and start the engine.

[dpaul]

Kind of what I thought
A10A is EWS challenge/response error.

The set of NFRM errors are all about lights out - if you don't have any lights non-functioning, you should recode the NFRM. Don't think this relates to the no start condition though

[BimmerMan2421]

Originally Posted by dpaul

Kind of what I thought
A10A is EWS challenge/response error.

The set of NFRM errors are all about lights out - if you don't have any lights non-functioning, you should recode the NFRM. Don't think this relates to the no start condition though

Could that A10A code be the reason for the no start issue? No matter how many times I erase the error memory, that code always pops back up and I've tried to figure out what the code means and how to fix it but no luck.

Regarding the FRM I had a right headlight bulb that was out and now the right angel eye bulb is out that I need to replace so that could be the reason for those FRM codes.

[dpaul]

Originally Posted by BimmerMan2421

Could that A10A code be the reason for the no start issue? No matter how many times I erase the error memory, that code always pops back up and I've tried to figure out what the code means and how to fix it but no luck.

Regarding the FRM I had a right headlight bulb that was out and now the right angel eye bulb is out that I need to replace so that could be the reason for those FRM codes.

Yes it could. To quickly summarize and perhaps over-simplify, EWS (theft protection) makes sure the DME and CAS have the same secret key. In the CAS (so-called CAS3+, >2009) the key is encrypted, in the DME key is stored in a memory location that is not easily accessible.

If these keys are not in alignment, the CAS will activate the starter but the DME will not provide ignition, so the engine cranks but doesn't start. Similarly, if something interrupts communication between CAS and DME during the exchange of key information, a code will be set and the engine will crank but not start. A10A is saying there was a problem with this communication

[BimmerMan2421]

Originally Posted by dpaul

Yes it could. To quickly summarize and perhaps over-simplify, EWS (theft protection) makes sure the DME and CAS have the same secret key. In the CAS (so-called CAS3+, >2009) the key is encrypted, in the DME key is stored in a memory location that is not easily accessible.

If these keys are not in alignment, the CAS will activate the starter but the DME will not provide ignition, so the engine cranks but doesn't start. Similarly, if something interrupts communication between CAS and DME during the exchange of key information, a code will be set and the engine will crank but not start. A10A is saying there was a problem with this communication

Wow dpaul thank you! I think you are definitely leading me towards the right direction regarding this issue, because as I stated earlier, I can always hear the fuel pump noises and humming whenever I unlock the car or open a door. Now I just need help on how to troubleshoot the A10A code and where to look that could be causing the code to repeatedly show up in the error memory.

Do you know where I can look first to see what's causing the communication problem in the CAS?

[dpaul]

Taking a step back, I am confused by your report that A10A is consistently observed i.e. immediately re-appears each time you clear it and yet the vehicle only very occasionally fails to start.

So I did a quick Google scan of A10A reports, and learned two things:
1) The true meaning of A10A is unclear - it may not indicate an EWS issue
2) There were a number of cases with persistent A10A (most but not all with starting problems) but none described a fix

When modules give odd errors that are not definitive this is my order of interventions:
Unplug connectors and clean
Look for corroded grounds or any other obvious wiring issue
Reset the module (NCSExpert SG_RESET)
Recode the module (NCSExpert SG_codieren, using "default" coding profile)
Reflash the module (WinKFP)

[tgeho_e92]

I replaced my starter and boom issue gone. Best hope!

[BimmerMan2421]

Ok I am back as I have finally had further time to run the car for codes using both INPA and ISTA. Also, the car didn't start for my sister a few days ago resulting in why I had to run for any codes.

What I found in ISTA from the tree is an error stored in the EKPS module that did not pop up in INPA. The code is 6293: Control Current Too High. Does anybody know what this means and how I can further diagnose what is causing a surge in the current? Could this explain why her car would crank but does not start due to no fuel being sent to create spark due to this EKPS error? Also I believe this is just a coincidence, but she states that when her car gives her this issue, it is usually always on a hot day.

To also add, car has ran fine for her for the past three days and I just checked today and car starts up fine and engine is running smooth. I will attach photos of the error code results as well as a test I ran on the CAS system to try and rule out any communication issues between the key, CAS module, and the DME.

[BimmerMan2421]

I think I may have found the reason why the car has issues with starting now. My sister has provided me with extra details when the issue occurs and it sounds like the EKP module is overheating causing no fuel to be sent to the engine. I just found a YouTube video with someone who had a similar issue and will try to do add thermal padding to the module and see if it helps the module. Hopefully this works and if anyone else runs into this issue, try this.

https://www.youtube.com/watch?v=Fjrd...oE9XChicagoE9X

[gbalthrop]

Originally Posted by BimmerMan2421

... codes using both INPA and ISTA. Also, the car didn't start for my sister a few days ago... The code is 6293: Control Current Too High. Does anybody know what this means and how I can further diagnose what is causing a surge in the current? [See Below]...

If the problem is ALWAYS on Startup, and NOT stalling while running (due to fuel pump shutting down), that suggests a failing pump that turns fine once started, but is "stuck" and won't turn properly when current is first applied after sitting. Such a "sticking" pump will BOTH (1) draw higher current / Amps than normal, and/or (2) Have a higher Temperature than normal (current drawn is related to Heat developed).

That SWAG is particularly likely if the "Crank, NO Start" situation happens after car has sat without engine running for a longer period, as opposed to being OFF for only a few minutes to a few hours. In that scenario, time NOT operated as opposed to heat developed in the tank or by normal pump rotation is the variable that explains what otherwise may appear "random".

That theory is supported by the Freeze Frame Data or Fault Details shown in your 2nd ISTA Screen. INPA and ISTA provide SO MUCH data, that you can easily overlook major CLUES which are contained in the data. In this case it isn't Flashing "Your Pump is STUCK" in Red Lights, but the data basically indicates that. Just to walk through that Data together:

1) The Definition of EKPS (Fuel Pump Module) Fault Code 6293 is "Control Current Too High".

2) When that Fault Code was saved in EKP Module Memory, it also saved certain system conditions, as measured by the EKP, at the INSTANT the fault was saved, providing a "Snapshot" of those conditions at that time.

3) Motor Current (draw) Electric Fuel Pump = 18.2 Amp.

4) Motor Speed Electric Fuel Pump = "0 1/min"; THAT'S ZERO RPM, rotation = NADA! STUCK while drawing 18.2 Amp Current. Watts (used to rate heaters ;-) = Volts x Amps. In YOUR case, instead of pumping fuel, your pump has turned into a HEATER (on that one occasion in the past) producing 185.64 Watts of heat, 'cuz it could NOT do work and pump fuel.

5) The fault was NOT currently present when you read fault code; the Pump Current draw value (Amps = 18.2) was too high, out of range = implausible; the German text NOT translated in your ISTA version = Fault would NOT (Kein) cause a Warning Lamp (MIL) to light (on Instrument Cluster).

6) The Fault was saved during Starter Cranking (Engine Speed = "200 1/min" or 200 RPM. No reason to check CAS Module, the Starter Cranked the engine, but the Fuel Pump was NOT pumping. Vehicle speed was Zero km/h, and your "Desert Air" was 39C.

7) The Reason Battery (Terminal 30) Voltage was only 10.3V, is NOT because the Battery was discharged. Battery voltage BEFORE pressing the START button was probably in 12.4V range, and the roughly 2.0 Volt DROP during Starter Cranking is Normal Voltage Drop due to Starter Draw.

I can't be quite certain WHY the Fuel Pump only occasionally refuses to turn. Perhaps someone who has conducted an "Autopsy" on a failed pump can provide that answer. Something to do with failing bearing, impeller contact, brushes (if any).
George