Engine Misfire

[RAFiK - BMWClubUAE]

Hey Guys,

I've been noticing that I am having a temporary misfire at Cold starts when the car has been parked for 24 hours or so.

It happens for just few seconds only when the car is cold and then goes back to normal idling. It is throwing codes of engine misfire on all cylinders.

Car info:
- 2008.03
- 64,000 kms
- Primary Cat Deleted (Don't know if that's useful)

Service & Other info:
- Sparks have been changed just 5,000 kms ago
- Oil is being changed every 5,000 kms
- Power is NOT affected at all and car is pulling hard without any weird noises. Behaves like it always did, nothing abnormal, it's just the cold start.


Any ideas?


Video:

[X5-User]

AFAIK, this happens a lot at cold start and there is a SIB about it which states that it is normal. As long as it doesn't through codes then you should be ok

[RAFiK - BMWClubUAE]

That's a good start and bit relieving!

Any other people?

[SenorFunkyPants]

Seems highly likely to be a fuel issue...not that up on the E9x M3 fuel system but I guess there are non return valves in the system and perhaps one is leaking?...causing a shortage of fuel on a start after standing for a while.

[///M Power-Belgium]

Originally Posted by RAFiK

That's a good start and bit relieving!

Any other people?

You have the cold start clunck noise too !
It happens at exactly 0:19 seconds runtime in your video ...

[RAFiK - BMWClubUAE]

Originally Posted by SenorFunkyPants

Seems highly likely to be a fuel issue...not that up on the E9x M3 fuel system but I guess there are non return valves in the system and perhaps one is leaking?...causing a shortage of fuel on a start after standing for a while.

Is there anyway to track that or inspect them somehow?

Originally Posted by ///M Power-Belgium

You have the cold start clunck noise too !
It happens at exactly 0:19 seconds runtime in your video ...

I'm not sure I'm following! Is the clunk noise bad? and at 0:19 the car was still off man lol! The first misfire happened around 0:28

[///M Power-Belgium]

Originally Posted by RAFiK

Is there anyway to track that or inspect them somehow?



I'm not sure I'm following! Is the clunk noise bad? and at 0:19 the car was still off man lol! The first misfire happened around 0:28

Like you said..Think you are not following..
It's just because you don't know the cold start clunck noise..
Most people don't notice it , because when the S65 starts there are a lot noises going on .
About the 0:19 sec. runtime..

You pushed your start button about 1.5 sec. "before" the 19 sec. runtime..
In other words the cold start clunck noise happens almost "during" the start .
So it happens about 1-1.5 sec. after you pushed your start button .
There are a lot S65's with the clunk noise when cold , this for over years..
Till today I saw only one true fix for this probem , and it was replacing the Vanos Gears .

I have it too , and the longer you don't drive the car the louder the clunck noise become .
When my car is garaged for a week or in winter for about 3-4 months to avoid road salt , I have it too .
But when DD , I don't have it .
Here is everything about the cold start clunck noise => http://www.m3post.com/forums/showthread.php?t=996069
And here is a very loud example of the clunck noise..
Note: It's "not" my car in the video .

[RAFiK - BMWClubUAE]

Originally Posted by ///M Power-Belgium

Like you said..Think you are not following..
It's just because you don't know the cold start clunck noise..
Most people don't notice it , because when the S65 starts there are a lot noises going on .
About the 0:19 sec. runtime..

You pushed your start button about 1.5 sec. "before" the 19 sec. runtime..
In other words the cold start clunck noise happens almost "during" the start .
So it happens about 1-1.5 sec. after you pushed your start button .
There are a lot S65's with the clunk noise when cold , this for over years..
Till today I saw only one true fix for this probem , and it was replacing the Vanos Gears .

I have it too , and the longer you don't drive the car the louder the clunck noise become .
When my car is garaged for a week or in winter for about 3-4 months to avoid road salt , I have it too .
But when DD , I don't have it .
Here is everything about the cold start clunck noise => http://www.m3post.com/forums/showthread.php?t=996069
And here is a very loud example of the clunck noise..
Note: It's "not" my car in the video .

Is it that SINGLE clunk noise that happened in the video?

I don't have that :S

[yuKon22]

I have the same thing occurring, 2010 e90 63k, lumpy idle, occasional misfire, had read that replacing the low pressure sensor resolved this, but after changeover no noticeable difference. The lower the air temp, the higher the probability it will occur from what I can tell...

[RAFiK - BMWClubUAE]

///M Power-Belgium

I listened to those noises in the other thread man and holy crap they are loud and nasty!!! I don't have that for sure! I keep my ears alert always.

I'll record a stereo voice note today using two microphones and post it here for you.

[RAFiK - BMWClubUAE]

yuKon22 It is hot summer in Dubai man with a basement temp of 32C!

[///M Power-Belgium]

Originally Posted by RAFiK

///M Power-Belgium

I listened to those noises in the other thread man and holy crap they are loud and nasty!!! I don't have that for sure! I keep my ears alert always.

I'll record a stereo voice note today using two microphones and post it here for you.

I'll repait...You had it at 19 seconds runtime , "but very slight" .
I listen always to videos with my head phone on , same thing for the videos with bearing failure with slight ticking or rattle noises .
And if you want to record another a video...
Advice..

Don't start/drive your car for about 2-3 days ,than record another video at cold start up and post it .. it only happens when the S65 is really cold , and it happens only once (1 x) in that same day .
And hold your cam in front of your S65 with the hood open , and I'm sure you will hear it too .

[aussiem3]

Originally Posted by RAFiK

Hey Guys,

I've been noticing that I am having a temporary misfire at Cold starts when the car has been parked for 24 hours or so.

It happens for just few seconds only when the car is cold and then goes back to normal idling. It is throwing codes of engine misfire on all cylinders.

Car info:
- 2008.03
- 64,000 kms
- Primary Cat Deleted (Don't know if that's useful)

Service & Other info:
- Sparks have been changed just 5,000 kms ago
- Oil is being changed every 5,000 kms
- Power is NOT affected at all and car is pulling hard without any weird noises. Behaves like it always did, nothing abnormal, it's just the cold start.


Any ideas?

I use to get the misfire when I have left the car with an almost empty tank of fuel. Since then I don't leave the tank empty even if I am not driving it. Now the car is almost a DD so no more issues in that department. Given where you live you, a full tank of fuel is a given, isn't it?

Like SFP said, it's fuel related.

[RAFiK - BMWClubUAE]

Originally Posted by ///M Power-Belgium

I'll repait...You had it at 19 seconds runtime , "but very slight" .
I listen always to videos with my head phone on , same thing for the videos with bearing failure with slight ticking or rattle noises .
And if you want to record another a video...
Advice..

Don't start/drive your car for about 2-3 days ,than record another video at cold start up and post it .. it only happens when the S65 is really cold , and it happens only once (1 x) in that same day .
And hold your cam in front of your S65 with the hood open , and I'm sure you will hear it too .

I'll do that and let you know, is it anything to worry about?

Originally Posted by aussiem3

I use to get the misfire when I have left the car with an almost empty tank of fuel. Since then I don't leave the tank empty even if I am not driving it. Now the car is almost a DD so no more issues in that department. Given where you live you, a full tank of fuel is a given, isn't it?

Like SFP said, it's fuel related.

It is not related to fuel level man, it has been happening for quite a while even with 90% fuel in. I'm not sure what it could be.

[///M Power-Belgium]

Originally Posted by RAFiK

I'll do that and let you know, is it anything to worry about?

Ok , Just let me know . ( PM me )
And worry about it ?
Probably not, because I saw some guys over here ..and they have it several years ,same thing here .

[BPMSport]

If you're getting a misfire fault for all cylinders, it's likely the idle air actuator. I would also replace the low pressure fuel sensor behind the air box.

[RAFiK - BMWClubUAE]

Could it be the MAF by any chance??

[RAFiK - BMWClubUAE]

Originally Posted by ///M Power-Belgium

Ok , Just let me know . ( PM me )
And worry about it ?
Probably not, because I saw some guys over here ..and they have it several years ,same thing here .

So an update, I do have that clunk noise but it is VERY minor and barely noticeable lol. I didn't record it unfortunately.

Now what is this clunk noise, why does it happen, and is it bad?

[///M Power-Belgium]

Originally Posted by RAFiK

So an update, I do have that clunk noise but it is VERY minor and barely noticeable lol. I didn't record it unfortunately.

Now what is this clunk noise, why does it happen, and is it bad?

Ahhhhhhh.....You see ! Voila like I said in your video => # 5 !
About your questions....
I repeat , till today I saw only one true fix for the clunck noise and it was replacing the Vanos-Gears and it's $$$$ !
Is it bad ?
Who knows , saw guys that have it several years so probably not , but it sounds not healty that's for sure ...
All I can do is post the link again => http://www.m3post.com/forums/showthread.php?t=996069
A question for you..
Is your car 6MT or DCT ?

[anom3]

For sure not normal, I do not get any sort of bounce like that when I cold start. I have the primary cat delete as well. Er... Akrapovic XPipe... So one set of cats is removed, but the smaller secondary ones are still there.

It does look like some sort of fuel supply issue though.

The order I would attack this, and I am no expert, so YMMV:

#1 - Empty the tank as much as you can (eg: drive around), and fill up with another brand of gasoline. See if this helps. Also BMW has its own "official" fuel system cleaner. I would try that as well.

#2 - #20 here -> http://www.realoem.com/bmw/enUS/show...diagId=16_0596

#3 - #13 here -> http://www.realoem.com/bmw/enUS/show...diagId=13_1241

All of the above of course depends on if / what codes the car is throwing... Knowing as much as I do on cold starts (believe me, I have done tons of research on cold starts to resolve another issue I had), the car TENDS to avoid throwing SOME codes right at cold start as things are a bit rough overall and then DME knows this...

--

Regarding the clunk, if you have a SINGLE clunk, its actually the alternator clutch.

http://www.m3post.com/forums/showpos...&postcount=422

Update : Weather its the actual alternator clutch, or something that is affected by the alternator kicking on I do not know. What I do know FOR SURE though is that by delaying when the alternator is thrown on (via IGR_DELAY @ JBE module) you delay when the SINGLE clunk takes place.

--

[SenorFunkyPants]

Originally Posted by anom3

Regarding the clunk, if you have a SINGLE clunk, its actually the alternator clutch.

http://www.m3post.com/forums/showpos...&postcount=422

Update : Weather its the actual alternator clutch, or something that is affected by the alternator kicking on I do not know. What I do know FOR SURE though is that by delaying when the alternator is thrown on (via IGR_DELAY @ JBE module) you delay when the SINGLE clunk takes place.

--

If true, thats a great spot - good job.

[RAFiK - BMWClubUAE]

Originally Posted by ///M Power-Belgium

Ahhhhhhh.....You see ! Voila like I said in your video => # 5 !
About your questions....
I repeat , till today I saw only one true fix for the clunck noise and it was replacing the Vanos-Gears and it's $$$$ !
Is it bad ?
Who knows , saw guys that have it several years so probably not , but it sounds not healty that's for sure ...
All I can do is post the link again => http://www.m3post.com/forums/showthread.php?t=996069
A question for you..
Is your car 6MT or DCT ?

It is 6MT

Originally Posted by anom3

For sure not normal, I do not get any sort of bounce like that when I cold start. I have the primary cat delete as well. Er... Akrapovic XPipe... So one set of cats is removed, but the smaller secondary ones are still there.

It does look like some sort of fuel supply issue though.

The order I would attack this, and I am no expert, so YMMV:

#1 - Empty the tank as much as you can (eg: drive around), and fill up with another brand of gasoline. See if this helps. Also BMW has its own "official" fuel system cleaner. I would try that as well.

#2 - #20 here -> http://www.realoem.com/bmw/enUS/show...diagId=16_0596

#3 - #13 here -> http://www.realoem.com/bmw/enUS/show...diagId=13_1241

All of the above of course depends on if / what codes the car is throwing... Knowing as much as I do on cold starts (believe me, I have done tons of research on cold starts to resolve another issue I had), the car TENDS to avoid throwing SOME codes right at cold start as things are a bit rough overall and then DME knows this...

--

Regarding the clunk, if you have a SINGLE clunk, its actually the alternator clutch.

http://www.m3post.com/forums/showpos...&postcount=422

Update : Weather its the actual alternator clutch, or something that is affected by the alternator kicking on I do not know. What I do know FOR SURE though is that by delaying when the alternator is thrown on (via IGR_DELAY @ JBE module) you delay when the SINGLE clunk takes place.

--

It is a single clunk, similar to the video M Power Belgium posted but VERY quiet and it is barely noticeable and that's why I was failing to notice it at the beginning.

I do appreciate your reply regarding the pressure sensors. So it is confirmed to be a fuel issue?

I ordered a DCAN Cable for my car and should reach in about a week, once it is here I'll post the fault codes for you to see them!

Much appreciated!