[rismo]

Indeed, my BMW dealer is stating after having the car returned 3 times for a cold start issue... that my DME might be corrupted.

What happend:

My car has issues with cold start in the mornings, shaking, revs going from 600 - 1200, limp modes) BT indicated a Fuel plausability code and a misfire both on cylinder 6

I brought her in and initialy they stated that it was normal for this engine... (statement of the head mechanic) ( I completly disagreed with him as the car is just 2 years and has 80000 km (aprox 50k miles) on it, and the car did not behave like this for the first 18 months)

The second time they replaced the HPFP and ignition coils + sparks, no improvement. They stated that the DME was corrupted and needs to be replaced, they had similair experience with another 335, but that one had a flash, and it sounded a bit like if tuned and this behaviour, then the DME should be corrupted...

The third time I insisted that they would replace the injector on cylinder 6 conform their own diagnostic analyses pdf and the given symptoms.

I picked up the car today and the behaviour is still there...

Now i'm a bit confused, could a piggyback damage a DME in such way that it would result in cold start issues?

Could it be that something has been shortcutted? The last month I drove without my tune (between fix 2 and fix 3) but the behaviour is still there..

If the DME is broken (repair will cost $2000) i might consider the BMW performance pack... but I can almost not believe that a damaged DME could cause this problem...

So I was wondering if other have similair experience even after they had a new injector....

[joec500]

if your DME is damaged...most likely your car would not work...or even turn on. Cold Start mis-fire is also a common problem.

Perhaps all you need is for BMW to update your DME with the latest BMW software.

[rismo]

I'm on a pretty recent software level... I always was on 29.2 but had to update for some other issue. This was done in september 09...

While writting and thinking out loud, maybe this recent software version could be the cause, but in that case other should also have experienced this behaviour..... I as fas as I have been performing research on this topic I have not read similair behaviour with a software cause... are there?

[blisstik]

Never heard of corrupted DME as an excuse not to update the software. Escalate the issue and hopefully it fixes the problem. Are you out of warranty or something?

[rismo]

My warranty ended on feb 2010... but I do not mind to pay to have the engine running normal...

I have been very open with my dealer about the tuning, and they always provided me warranty repairs...

They even installed my non standard brake pads, they take my procede out when required for testing, they installed the helix FMIC and my DCI...

But now.... the relationship is a bit cooled down.... I did not demand an software update but this might be an option before opting for a new DME...

Are there known cold start issues with certain DME software versions?

[shifterboy45]

the answer is yes --

does it happen often -- no

like any other electronic component it can exhibit certain behavioral patterns that lead to the need to replace it.. especially in the case of systemic elimination of possible problem components --eg. injectors, plugs, etc.

can a software upgrade cause a problem, yes --
most of the time if this occurs, the problem will manifest right after the new software is installed ..

if the shop is seeing a list of fault codes that are not remedied by a part replacement then its a good chance it may be the DME.

the problem nowadays is that to replace the DME it must be coded to the car.. which limits you and the shop to very narrow options. if the DME is not the cause of the failure .. the parts dept wont want to except it back as it has been coded to your car.... in the old days we could pull a DME off the shelf and test the car with it and if it didnt solve the problem -- rebox it and slap your old DME back into the car.

so they need to be sure that its "really" the DME -- and not something else, like a engine wiring harness problem.. i doubt the Procede caused the problem but if it turns out there "is" a wiring harness problem it may have resulted from the installation...

does the shop know you have had a tune installed? if not .. you may wanna clue them, if you can --

cheers

[rismo]

does the shop know you have had a tune installed? if not .. you may wanna clue them, if you can --

Yes they are fully aware of the tuning and provided all support with it...

Originally Posted by rismo123

They even installed my non standard brake pads, they take my procede out when required for testing, they installed the helix FMIC and my DCI...

But now.... the relationship is a bit cooled down.... I did not demand a new are update yet, but this might be an option before opting for a new DME...

@ShifterBoy,

May I ask if you have an background in this expertise?
I have studied Industrial IT / Automation myself and I'm quite familair with these kind of software solutions... not about this DME but more in the general concepts... of course electronics can die... especially by electrical interference.. but I consider that very rare especially give the case holding the DME hardware...

Normally cold start issues sound to me more like a DI engine problem..

But not be ignorant, I will check all DME related connectors to see if there is anything wrong.. I did not do that yet as it is freezing over here :-) and I do not have a garage...

[CBR335]

Wow, that is some dealer. It sounds like now that you are out of warranty, they would like you to pick up the tab for repairs.........

Damage to the DME sounds unlikely, but damage to one of the harnesses due to repeated installation and removal of the piggyback is very possible. Perhaps a fuel regulation issue due to a faulty connector?

[shifterboy45]

Originally Posted by rismo123

Yes they are fully aware of the tuning and provided all support with it...







@ShifterBoy,

May I ask if you have an background in this expertise?

yes.. i have a few weeks training -- j/k -- i have worked the some of the first on-board computer systems for autos in the late 70's and early 80's ..
(GM15a and tune up technician) -- also my first "slug" from BMW in 1988 on the E32 (7series) complete training, and a few other one besides...

I have studied Industrial IT / Automation myself and I'm quite familair with these kind of software solutions... not about this DME but more in the general concepts... of course electronics can die... especially by electrical interference.. but I consider that very rare especially give the case holding the DME hardware...

true.. that is why I would lean toward an issue with the harness ... there have been quite a few DMEs replaced, (in the old days) that were reinstalled due to a open circuit or a resistance issue in the engine harness.. thats why i made that comment.

Normally cold start issues sound to me more like a DI engine problem..

there could be a bad signal to the throttle motor, or a number of other things that would cause the car to "hunt" for idle when cold.. and the throttle opening and closing erratically would trip the SES light.. so i would only condemn the DME if its truely the failed component.. but I think there is a little more TroubleShooting in order.. but then again that one mans opinion

But not be ignorant, I will check all DME related connectors to see if there is anything wrong.. I did not do that yet as it is freezing over here :-) and I do not have a garage...

sorrry for the cold weather

[rismo]

You mention this is an issue when cold - does everything go away after the engine warms up? Does it happen on warm starts?

Only on cold start. After the moment that the car is driven 1 or 2 minutes it's gone.

Never on warm startups.

Another long shot - is their a GIAC dealer near you that could possibly re-write the flash? Maybe even throw their code over the top for testing purposes?

What would be the difference to put a GIAC flash on the car instead of a BMW software update?

My only tune is the Procede, the DME software is original BMW.

[JoeyFiasco]

Originally Posted by CBR335

Wow, that is some dealer. It sounds like now that you are out of warranty, they would like you to pick up the tab for repairs.........

Damage to the DME sounds unlikely, but damage to one of the harnesses due to repeated installation and removal of the piggyback is very possible. Perhaps a fuel regulation issue due to a faulty connector?

that's a good point.

[rismo]

Originally Posted by shifterboy45

sorrry for the cold weather

LOL... ;-)

Quote:
Originally Posted by CBR335
Wow, that is some dealer. It sounds like now that you are out of warranty, they would like you to pick up the tab for repairs.........

Damage to the DME sounds unlikely, but damage to one of the harnesses due to repeated installation and removal of the piggyback is very possible. Perhaps a fuel regulation issue due to a faulty connector?

that's a good point.

I will put on some warm clothes and check the wiring this afternoon... (I believe that this should be the proper next step... everything else is guesing.. ;-) Local saying says: "To know is to measure / validate".... )

But just for my understanding and interest, is each cylinder fueling managed by it's own wire?
As logging indicates only problems with cylinder 6....

[rismo]

Check the cables around the DME... all seems to be normal and connected...

Problem is still there...

I will add the BT codes to this thread...


Next: Request a software update?

[blisstik]

Check cylinder 6 to make sure the ignition coil is actually all the way in. If you have the spark plug tool, make sure its not loose. Then check with BT.

If it still shows up, clear the codes and swap ignition coil 6 with 5 then check again with BT. If it shows up on 5, its the coil. If it shows up on 6, its the spark plug or fuel injectors.

I really doubt its a corrupted DME. Sounds more like a corrupted dealer. Did they really swap out all plugs and coils?

[rismo]

I have seen the repair sheets, there it stated that they replaced the HPFP and coils... alse they showed me the replacement worksheet of the injector...

But to be honest, i'm not that sure anymore about this dealer...

The testing part is a bit harsh as it only shows up on cold start and not always dropping a code... only when the engine realy goes crazy (neigbours watching the car think that it might explode at that time ;-)) but even when there is no code dropped, my non technical girlfriend is even sensing the instable engine behaviour... and she doesn't even know the difference between a volkswagen and a BMW...

One thing the SA mentioned is that they think the car is running to rich while idle... giving the fuel plausibilty code....

[joec500]

O2 Sensors could be damaged.

[shifterboy45]

Originally Posted by rismo123

I have seen the repair sheets, there it stated that they replaced the HPFP and coils... alse they showed me the replacement worksheet of the injector...

But to be honest, i'm not that sure anymore about this dealer...

The testing part is a bit harsh as it only shows up on cold start and not always dropping a code... only when the engine realy goes crazy (neigbours watching the car think that it might explode at that time ;-)) but even when there is no code dropped, my non technical girlfriend is even sensing the instable engine behaviour... and she doesn't even know the difference between a volkswagen and a BMW...

One thing the SA mentioned is that they think the car is running to rich while idle... giving the fuel plausibilty code....

this really sound like a throttle motor/harness problem to me...

i know for a fact there is hunting condition on the N52's that require a throttle motor replacement... this by experience, by 2007 328iC did the same thing, erratic idle for a short period in the morning, but in my case, there was no SES light and if i hadnt told the tech the situation -- and replicate the problem they were going to ship my car ... with no repair..

has the shop duplicated the conditon(s) .. ??? i mean let it cool down overnight and start it first thing in the morning?

hunting idle is not a normal condition, and the fuel plausiblilty is probably due to the over-rich condition with the idle fluctuating during the cold enrichment phase...

and there are some parts that will not set a fault code in memory .. like the air mass meter on vehicles (ie X5)... ill try to look up the SIB in relation to this -- but remember it may be N52 specific -- thus may not apply to your car.. but ill do a search tomorrow when it get back in..

cheers -- and sorry i cant give you a definitive answer.. being that is all remote / hypothetical diagnosis

[shifterboy45]

Originally Posted by rismo123

Indeed, my BMW dealer is stating after having the car returned 3 times for a cold start issue... that my DME might be corrupted.

What happend:

My car has issues with cold start in the mornings, shaking, revs going from 600 - 1200, limp modes) BT indicated a Fuel plausability code and a misfire both on cylinder 6

I brought her in and initialy they stated that it was normal for this engine... (statement of the head mechanic) ( I completly disagreed with him as the car is just 2 years and has 80000 km (aprox 50k miles) on it, and the car did not behave like this for the first 18 months)

The second time they replaced the HPFP and ignition coils + sparks, no improvement. They stated that the DME was corrupted and needs to be replaced, they had similair experience with another 335, but that one had a flash, and it sounded a bit like if tuned and this behaviour, then the DME should be corrupted...

The third time I insisted that they would replace the injector on cylinder 6 conform their own diagnostic analyses pdf and the given symptoms.

I picked up the car today and the behaviour is still there...

Now i'm a bit confused, could a piggyback damage a DME in such way that it would result in cold start issues?

Could it be that something has been shortcutted? The last month I drove without my tune (between fix 2 and fix 3) but the behaviour is still there..

If the DME is broken (repair will cost $2000) i might consider the BMW performance pack... but I can almost not believe that a damaged DME could cause this problem...

So I was wondering if other have similair experience even after they had a new injector....

after reading the list of complaints on the car,

i did a quick symtom search,

1 you have a SES light on

2 you have a fuel plausiblity code set (which one you did not indicate)

3 the vehicle runs poorly -

have the shop verify if they have looked at SIB 12 55 06

its a March 2010 bulletin affecting 06/06 and later E9x cars

under Situation II

HTH

ps
check and make sure they have the lastest software on the DME before condemning it --

In addition, vehicles which have had the HDP pump replaced have to be reprogrammed afterwards with ISTA/P 2.37.0 (or higher).

[shifterboy45]

Originally Posted by DanE92

So what you are saying.BMW does change, upgrade sotfware with new HPFP instals???

currently its a requirement for any HDP replacement

i noted in another post that the new ISTA/P version there were some improvements in the functionality and diagnostic in that particular system.

and with the elimination of the 881 pump, and use of the new 943 it looks like software version upgrades are not just suggested .. its mandated

but to note:

this doesnt mean in the OP instance it is the pump, but im trying to rule out all other possibilities

[vase330]

Originally Posted by rismo123

I have seen the repair sheets, there it stated that they replaced the HPFP and coils... alse they showed me the replacement worksheet of the injector...

But to be honest, i'm not that sure anymore about this dealer...

The testing part is a bit harsh as it only shows up on cold start and not always dropping a code... only when the engine realy goes crazy (neigbours watching the car think that it might explode at that time ;-)) but even when there is no code dropped, my non technical girlfriend is even sensing the instable engine behaviour... and she doesn't even know the difference between a volkswagen and a BMW...

One thing the SA mentioned is that they think the car is running to rich while idle... giving the fuel plausibilty code....

My car used to shake shudder miss and cough on cold start too. I had software update, it improved a whole lot, but its still shakes and shudders a bit for a few minutes and stabilizes. Nothing unbearable, but its still there even if it feels like only a fraction the intensity of the previous behavior. Something about the N54 running kind of crapy like a diesel seems to be the norm. If its that violent in your case, do you smell raw unburned gas?

[shifterboy45]

qoute:

The testing part is a bit harsh as it only shows up on cold start and not always dropping a code... only when the engine realy goes crazy (neigbours watching the car think that it might explode at that time ;-)) but even when there is no code dropped, my non technical girlfriend is even sensing the instable engine behaviour... and she doesn't even know the difference between a volkswagen and a BMW...

unqoute:

this is the reason i feel that it may be the harness/EDK motor.. but its diligent to ask if its the current ISTA/P release version. (as a starting point)

plus- a engine harness / or throttle motor is not "coded" to the car like the DME is, and with that in mind the remove and replace if not bad scenario could play out -- depending on their shop policy. plus there are significantly less (cost wise) than a DME replacement.

its time consuming, and labor intensive to t/s a problem that does not set a failure/problem code, and depending on the level of experience in the shop with this type of problem may limit them to the scope of actual experience.

[rismo]

Hi Guys,

Just a quick one, thank you very much for all the feedback. I have been flying all week for business, but I will get back to this tommorow....

Nick / Shifterboy, thanks for your input!
I think next step should be a software update... but if they replaced the HPFP in the past with the former model, is an update in that case still required?