[Amizzi]

Hi everyone,

I have a really annoying missfire going on at idle that absolutely driving me F!@#ing nuts!!!

I have done a lot of research on this issue and tried a bunch of things already but I can't seem to beat this, I'm just wondering if anyone else can provide any more helpful advice that may aid me.
Trying to find other options and anything else I can potentially try before burning an even bigger hole in my pocket.

As I have mentioned the missfire is during idle when the engine is warm or cold, there are no codes that are logged currently.

The following is what has been done fairly recently in regards to fuel/ignition .
I love this car and I know obviously that repairs can be costly but this is getting out of hand now, the following repairs listed are just the tip of the iceberg that pertain to the possible missfire problem.
The car is an 07 335xi and currently has 108,000km.

-x3 injectors bank 1 replaced @ 53,420km

-x3 injectors bank 2, x6 spark plugs, x6 coils replaced @ 60,285km

-x3 injectors x2 bank1/x1 bank2, HPFP, x3 fouled spark plugs replaced with corresponding injectors @ 73,480km

-x6 injectors replaced @ 81,564km

Just recently performed/replaced @ 107,400km
-Walnut blasting
-x6 spark plugs replaced
-x6 coils replaced

Thanks for any help guys,
Adrian

[jwebb335xi]

Originally Posted by Amizzi

Hi everyone,

I have a really annoying missfire going on at idle that absolutely driving me F!@#ing nuts!!!

I have done a lot of research on this issue and tried a bunch of things already but I can't seem to beat this, I'm just wondering if anyone else can provide any more helpful advice that may aid me.
Trying to find other options and anything else I can potentially try before burning an even bigger hole in my pocket.

As I have mentioned the missfire is during idle when the engine is warm or cold, there are no codes that are logged currently.

The following is what has been done fairly recently in regards to fuel/ignition .
I love this car and I know obviously that repairs can be costly but this is getting out of hand now, the following repairs listed are just the tip of the iceberg that pertain to the possible missfire problem.
The car is an 07 335xi and currently has 108,000km.

-x3 injectors bank 1 replaced @ 53,420km

-x3 injectors bank 2, x6 spark plugs, x6 coils replaced @ 60,285km

-x3 injectors x2 bank1/x1 bank2, HPFP, x3 fouled spark plugs replaced with corresponding injectors @ 73,480km

-x6 injectors replaced @ 81,564km

Just recently performed/replaced @ 107,400km
-Walnut blasting
-x6 spark plugs replaced
-x6 coils replaced

Thanks for any help guys,
Adrian

This may have been done with the last injector swap, but have you confirmed same index with injectors on each bank AND that they are coded?

Cleaned VANOS solenoids?

What do you mean by "misfires?" If you're not getting any codes, this could very well be a "stumble" not related to fuel or spark at all.

Mods?

Are you running a tune? Can we get a log if you have the ability to do so?

Without any more info it's impossible for us to guess. Could be a vacuum leak, TMAP issue, throttle body, etc.

[E92er]

I had a similar situation after performing a valve cleaning. My symptoms were only at idle as well and no codes. Car would stumble and at the beginning of idle the rpm were higher than normal. Some how my new seals for the manifold and throttle body were misplaced so I reused my old ones. That caused my whole issue. Installed new seals and all was well again.

[Amizzi]

Forgot to mention yes Vanos Solenoids were cleaned @ 106,000km, I have not however confirmed same index with injectors so I will do that next.

Mods are as follows:
-Cobb CP
-JB4
-Cat-back Exhaust
-7" VRSF fmic
-BMS DCI

There's a bit of a stumble and most definitely a subtle missfire aswell, I guess not severe enough to give a code. Its a little harder to hear it from the interior, but sitting next to the engine with the hood open or sitting by the exhaust it can clearly be heard at idle. Once the rpms are increased it disappears and runs smoothly.

I am going to go for a drive tonight and take some logs and even some audio of the missfire.

E92er made a comment that he had to use his old gaskets for the throttle body and intake manifold which caused a similar issue, this reminded me that when I had done the walnut blasting and was re-installing the manifold I accidentally dropped one of the gaskets for the manifold into the engine bay and couldn't find it resulting in me having to re-use 1 of the old ones.......has me wondering now if that might be the culprit ???

Thanks again guys for your help!
Adrian

[mike@x-ph.com]

You either have a bad fuel pump or injectors need to coded
Are you sure all your injectors are same index?