[shawntech]

08 335xi, still under cpo, stock hardware, 92k miles.

Upon cold start and putting into gear mild shudder/roughness is felt. I have inpa lpfp is reading around 5000 hpa hpfp 50000 hpa, fuel trims around +3/4%. Zero codes stored, drivability and power delivery are perfect just off idle and when warm disappear completely.

Am I dealing with an injector issue? Plugs are 3k old there is no misfire so what do I do? Bring it in leave overnight and have them start it in the morning to experience the cammed v8 effect at low rpm? I suppose it could be carboned up valves but its smooth as glass above idle and idle is fine once operating temperature is met.

Seems pretty much impossible to troubleshoot short of pulling plugs overnight and checking bores for fuel dilution. Any tests/data I can reference in inpa to go in the right direction?

Car did get 4 new jects under recall in 2011 before I bought it as well as a rear turbo and hpfp. Aside from dodgy cold start behavior that just began it runs perfectly including idle once at operating temperature.

Ofh was done by cpo 3k ago which meant intake manifold off, would they have made mention or addressed carbon problem at that time?

I guess I now join the ranks of the troubleshooting brigade. Also worth mention wot bank 2 is always +8% over bank 1, most logs I view are consistent however afr is maintained.

More knowledgeable than me, please chime in

[j1gilles]

Let it sit overnight and start it. Let it run for a few seconds and then shut it off. Pull your plugs and look for "wet" plugs.

[akotten]

If it's bad enough, you should have misfire codes. When this happened to me on cold starts, it ended up being leaking injectors. I just replaced all six so I could be done with it. Purrs ever since...minus a few hiccups from never cleaning the intake valves with 120k miles.

[shawntech]

getting the intake ports cleaned Monday, it's my understanding warranty/cpo doesn't matter and they may suggest this anyway for a lot of money out of my pocket so I might as well get it out of the way, hope it fixes the problem and if it doesn't... to the dealer it goes.

Also put some techron in, some have had success with this cleaning up injectors *shrug*

I also noticed in INPA cyl2 at warm idle was in the "black" at 39ms pwm, while the rest were 43-45pwm... not sure if this matters at all.

[vasillalov]

Most probably you have a leaky injector.

[shawntech]

regarding "leaking injectors" how does warranty deal with this if there is no code and it only causes drivability problems in the morning?

[shawntech]

had intake ports walnut blasted did not change anything, poking around in INPA the only thing out of place I see is injector #2 PWM is lower than the other 5 and the injector voltage is below range at 128v vs 135-138v for the other cylinders.

any ideas people?

[Miller335]

Originally Posted by ls3c6

had intake ports walnut blasted did not change anything, poking around in INPA the only thing out of place I see is injector #2 PWM is lower than the other 5 and the injector voltage is below range at 128v vs 135-138v for the other cylinders.

any ideas people?

You should verify the injector codes on each injector and see if it matches what INPA says.

[shawntech]

Originally Posted by Miller335

You should verify the injector codes on each injector and see if it matches what INPA says.

did that as well, they do match calibration.

[akotten]

Originally Posted by ls3c6

regarding "leaking injectors" how does warranty deal with this if there is no code and it only causes drivability problems in the morning?

Eventually, they will leak bad enough to were the cylinders will just be flooded out and it will not return to normal operation until you replace them. That is what happened to me. It will leave your car immobile eventually. So hopefully you live close to a dealer or have the tools to do it yourself like I did. Be ready to replace spark plugs too, as they will be badly fouled after this occurs.

[shawntech]

Originally Posted by akotten

Eventually, they will leak bad enough to were the cylinders will just be flooded out and it will not return to normal operation until you replace them. That is what happened to me. It will leave your car immobile eventually. So hopefully you live close to a dealer or have the tools to do it yourself like I did. Be ready to replace spark plugs too, as they will be badly fouled after this occurs.

*sigh* I'm hoping to get it resolved before that happens and takes out other parts, maybe I should just put a set of injectors in it myself. Current ones are all index 06-09

[bigdaddycane]

I'm not sure if you stated it in one of the posts above, but have the valve cleaning done at an Indy shop NOT the dealer.

[shawntech]

Originally Posted by bigdaddycane

I'm not sure if you stated it in one of the posts above, but have the valve cleaning done at an Indy shop NOT the dealer.

Intake ports were cleaned at an indy with before/after pictures... honestly I haven't noticed any difference in drivability (I also reset adaptions when they were done)

[Myrder]

money on leaky injector.

[Dmacc]

Originally Posted by Myrder

money on leaky injector.

+1, was just dealing with this exact issue. Valve cleaning done, no change, swap all injectors to new part number, fixed all issues.

[shawntech]

Originally Posted by Dmacc

+1, was just dealing with this exact issue. Valve cleaning done, no change, swap all injectors to new part number, fixed all issues.

you did it or dealer did? I have no faults so I'm not sure they'll do anything

[Dmacc]

Originally Posted by ls3c6

you did it or dealer did? I have no faults so I'm not sure they'll do anything

Dealer fixed it. I'm cool with my SA and under CPO, I told him the issues, laggy throttle, lumpy start ups, wet plugs, and he got me all sorted with new injectors coded, 6 new plugs and out the door under warranty. I too didn't have any faults, but when driving the car it was obvious something was wrong.

[e90Mark]

I did walnut blast, plugs, and coils.. It's leaky injectors for me. Just to give you an idea the initial cost is like $1600 for all 6 at the dealer.

[shawntech]

Originally Posted by e90Mark

I did walnut blast, plugs, and coils.. It's leaky injectors for me. Just to give you an idea the initial cost is like $1600 for all 6 at the dealer.

I have CPO but I can code/replace the injectors myself, i'll do yours less than $1600 LOL

[e90Mark]

Right, I read the OP but just letting you know.
I'm capable of doing mine, but I have a good relationship with my SA and it's going to cost me what it would to DIY, so I'll let them handle it.

[shawntech]

bump, butt still shaking at cold start but no faults