3.0i M54 Rough idle then cuts out

[enuff_zed]

Well I finally got time to look further into this issue.
Fitted another throttle body, checked all the connections and hoses, cleaned the ICV again just to be sure.
Put it all back together, did a full reset of adaptations, and exactly the same problem.
Today's codes are:
2830 DME self-test: checksum
2796 Throttle: adaptation values incorrect
28B2 Speed limitation: reset

Then, within the DSC side of things I have the warning light on and these codes:
5E18 CAN data fault from DME/DDE
5E19 CAN data fault from DME/DDE(DSC lamp on as long as error is present)

I still have the situation where if I do a fault reset with the engine running then it settles perfectly for about 10 seconds and I have full throttle control.
Then it dies again. So that seems like it is running on some kind of default setting while the systems do a self test.
Again, disconnecting the MAF makes no difference.

bigwinn is popping over next week and we're hoping he can reflash the DME, but who knows.

Any other suggestions?

[spazmochad]

Well I finally got time to look further into this issue.
Fitted another throttle body, checked all the connections and hoses, cleaned the ICV again just to be sure.
Put it all back together, did a full reset of adaptations, and exactly the same problem.
Today's codes are:
2830 DME self-test: checksum
2796 Throttle: adaptation values incorrect
28B2 Speed limitation: reset

Then, within the DSC side of things I have the warning light on and these codes:
5E18 CAN data fault from DME/DDE
5E19 CAN data fault from DME/DDE(DSC lamp on as long as error is present)

I still have the situation where if I do a fault reset with the engine running then it settles perfectly for about 10 seconds and I have full throttle control.
Then it dies again. So that seems like it is running on some kind of default setting while the systems do a self test.
Again, disconnecting the MAF makes no difference.

bigwinn is popping over next week and we're hoping he can reflash the DME, but who knows.

Any other suggestions?

Don't rule out the alternator - I've just replied in your other thread about the DME updates before noticing your thread here. I had very similar issues which after replacing a lot of stuff, turned out to be the alternator. Having checked the voltage output was correct when the stalls originally began happening and since I had replaced the regulator already a few years ago, I originally ruled it out.

Only came to replace it since the bearings were noisy, which was driving me nuts trying to diagnose the engine stalling issue.

I should mention I also replaced the oil level sensor at the same time since it was bad and had heard those can cause CAN bus issues on an E46.

After that the stalling stopped. I think I went through about 3 different replacement alternator vendors before I finally found a good refurbished Bosch unit from a Bosch factory with the correct seals and tag.

Stuff to bear in mind

[enuff_zed]

Well I finally got time to look further into this issue.
Fitted another throttle body, checked all the connections and hoses, cleaned the ICV again just to be sure.
Put it all back together, did a full reset of adaptations, and exactly the same problem.
Today's codes are:
2830 DME self-test: checksum
2796 Throttle: adaptation values incorrect
28B2 Speed limitation: reset

Then, within the DSC side of things I have the warning light on and these codes:
5E18 CAN data fault from DME/DDE
5E19 CAN data fault from DME/DDE(DSC lamp on as long as error is present)

I still have the situation where if I do a fault reset with the engine running then it settles perfectly for about 10 seconds and I have full throttle control.
Then it dies again. So that seems like it is running on some kind of default setting while the systems do a self test.
Again, disconnecting the MAF makes no difference.

bigwinn is popping over next week and we're hoping he can reflash the DME, but who knows.

Any other suggestions?

Don't rule out the alternator - I've just replied in your other thread about the DME updates before noticing your thread here. I had very similar issues which after replacing a lot of stuff, turned out to be the alternator. Having checked the voltage output was correct when the stalls originally began happening and since I had replaced the regulator already a few years ago, I originally ruled it out.

Only came to replace it since the bearings were noisy, which was driving me nuts trying to diagnose the engine stalling issue.

I should mention I also replaced the oil level sensor at the same time since it was bad and had heard those can cause CAN bus issues on an E46.

After that the stalling stopped. I think I went through about 3 different replacement alternator vendors before I finally found a good refurbished Bosch unit from a Bosch factory with the correct seals and tag.

Stuff to bear in mind

Wow, that's a bit left of field. Would never have considered that.

[bigwinn]

Well I finally got time to look further into this issue.
Fitted another throttle body, checked all the connections and hoses, cleaned the ICV again just to be sure.
Put it all back together, did a full reset of adaptations, and exactly the same problem.
Today's codes are:
2830 DME self-test: checksum
2796 Throttle: adaptation values incorrect
28B2 Speed limitation: reset

Then, within the DSC side of things I have the warning light on and these codes:
5E18 CAN data fault from DME/DDE
5E19 CAN data fault from DME/DDE(DSC lamp on as long as error is present)

I still have the situation where if I do a fault reset with the engine running then it settles perfectly for about 10 seconds and I have full throttle control.
Then it dies again. So that seems like it is running on some kind of default setting while the systems do a self test.
Again, disconnecting the MAF makes no difference.

bigwinn is popping over next week and we're hoping he can reflash the DME, but who knows.

Any other suggestions?

Don't rule out the alternator - I've just replied in your other thread about the DME updates before noticing your thread here. I had very similar issues which after replacing a lot of stuff, turned out to be the alternator. Having checked the voltage output was correct when the stalls originally began happening and since I had replaced the regulator already a few years ago, I originally ruled it out.

Only came to replace it since the bearings were noisy, which was driving me nuts trying to diagnose the engine stalling issue.

I should mention I also replaced the oil level sensor at the same time since it was bad and had heard those can cause CAN bus issues on an E46.

After that the stalling stopped. I think I went through about 3 different replacement alternator vendors before I finally found a good refurbished Bosch unit from a Bosch factory with the correct seals and tag.

Stuff to bear in mind

Wow, that's a bit left of field. Would never have considered that.

I can bring an alternator on Wednesday bud?

[enuff_zed]

Don't rule out the alternator - I've just replied in your other thread about the DME updates before noticing your thread here. I had very similar issues which after replacing a lot of stuff, turned out to be the alternator. Having checked the voltage output was correct when the stalls originally began happening and since I had replaced the regulator already a few years ago, I originally ruled it out.

Only came to replace it since the bearings were noisy, which was driving me nuts trying to diagnose the engine stalling issue.

I should mention I also replaced the oil level sensor at the same time since it was bad and had heard those can cause CAN bus issues on an E46.

After that the stalling stopped. I think I went through about 3 different replacement alternator vendors before I finally found a good refurbished Bosch unit from a Bosch factory with the correct seals and tag.

Stuff to bear in mind

Wow, that's a bit left of field. Would never have considered that.

I can bring an alternator on Wednesday bud?

I'll try to get some voltage output readings off it to be sure.
I'll let you know, cheers.

However, it has gone through 100s of start cycles over the last few days and the battery seems quite happy.............

[Chris_D]

it's the ccv diaphragm. am tellin ye.

[enuff_zed]

it's the ccv diaphragm. am tellin ye.

So why does it run perfectly when you reset it? Sounds much more electrical and less basic physics to me?

[Chris_D]

it's the ccv diaphragm. am tellin ye.

So why does it run perfectly when you reset it? Sounds much more electrical and less basic physics to me?

Idk. Maybe like how my knackered throttlebody would work fine when you reset it. Then on the next startup it would go kerplup and die.

Dont forget that a lot of components work fine outside of operational parameters/limits set by the dme.

[enuff_zed]

it's the ccv diaphragm. am tellin ye.

So why does it run perfectly when you reset it? Sounds much more electrical and less basic physics to me?

Idk. Maybe like how my knackered throttlebody would work fine when you reset it. Then on the next startup it would go kerplup and die.

Dont forget that a lot of components work fine outside of operational parameters/limits set by the dme.

Worth a look at least

[Rix]

How did the reflash go? Any joy?

[enuff_zed]

How did the reflash go? Any joy?

Still only Monday in Norfolk mate!
I did say we're doing it Wednesday (or maybe Saturday to you )

[Rix]

Duh, ignore me!! Fingers crossed....

[IRD]

Martin/Stuart et al. I really enjoy reading the posts. I just wish I understood what they were all about, especially all those acronyms. I hope Wednesday is a better day weather wise than today and that all goes well.

[enuff_zed]

Martin/Stuart et al. I really enjoy reading the posts. I just wish I understood what they were all about, especially all those acronyms. I hope Wednesday is a better day weather wise than today and that all goes well.

Cheers.
Acronym is easy. DME is the ECU for the engine.

[IRD]

Martin/Stuart et al. I really enjoy reading the posts. I just wish I understood what they were all about, especially all those acronyms. I hope Wednesday is a better day weather wise than today and that all goes well.

Cheers.
Acronym is easy. DME is the ECU for the engine.

Thanks Martin. Every day is a school day. Joking apart. It is impressive to see the range of knowledge and expertise available on the Forum. Imagine what the cost would be if you had seek help from a main dealer.