[MSport35TT]

Hello All,

I have a 335xi N54. It was in for service 2 weeks ago for misfiring. They determined it was caused by fouled out spark plugs and fuel injectors along with a sensor here and there. All was covered by warranty thank the good Lord. Previously I had a Cobb stage 1 installed which I believe to accelerate the wear and tear on the select parts, so before i serviced the car I uninstalled. The car was serviced with no questions asked.

I had the car back for a week and notice a slight hick-up at a stand still and was concerned that the issues were not completely solved. I again did the uninstall of the Cobb 20 mins before bringing it in for service and now I am waiting the results. I called my SA and he said that they see its a timing issue but need to get BMW to test the computer for further diagnostics.

I have hear that Cobb may leave an image behind even after uninstalling the tune. Does anyone believe there is anything to worry about regarding my warranty at this point? If so any questions I should be prepared to answer? Lastly, would it be an option to try a different tune at this point? Thank you all in advance for you input.

[Jeff@TopGearSolutions]

Timing issue? That's quite broad.

You will be ok, just let them fix the problem, this car has a bunch of quirks about it even on stock tune. The cobb is sound.

[JamesM3M5]

Sounds like you have the dreaded low RPM/idle hiccup. Mine has come back very slightly after changing: plugs, pre-cat O2 sensors, cleaning both MAP sensors, intake cleaning (once when I bought it, once again a year later to see how fast it builds up), cleaning the valve cover internals and cleaning the PCV inside the valve cover, new VC gasket with sealant in the critical areas, and all new injectors. Unrelated items changed are the low pressure pump and low pressure sensor (died).

My plugs are getting long in the tooth for having a Procede and PWM meth for over 16k miles now, so I will try that again. I also have a new Dinan lightened dual-mass flywheel and clutch to go in, but I was incredibly sick over Christmas and all that has been pushed back. The only other thing I can think of is a misfire, or the DME perceives a misfire, due to a worn out springing medium in the DMFW. The very high HP N54s are having a misfire at high load/high RPM possibly due to the dual-mass flywheel, so I am speculating that the DMFW may cause issues at lower RPMs/loads, too. I have 65k miles on mine now.

The one thing that cleared up my idle and low RPM hiccups most noticeably was cleaning the MAP sensors, especially the one in the intake manifold. They get oiled/carbon fouled. Also changing the pre-cat O2 sensors significantly reduced the hiccups, too.

[themyst]

Valve cleaning for rough/inconsistent idle maybe?

[MSport35TT]

Originally Posted by JamesM3M5

Sounds like you have the dreaded low RPM/idle hiccup. Mine has come back very slightly after changing: plugs, pre-cat O2 sensors, cleaning both MAP sensors, intake cleaning (once when I bought it, once again a year later to see how fast it builds up), cleaning the valve cover internals and cleaning the PCV inside the valve cover, new VC gasket with sealant in the critical areas, and all new injectors. Unrelated items changed are the low pressure pump and low pressure sensor (died).

My plugs are getting long in the tooth for having a Procede and PWM meth for over 16k miles now, so I will try that again. I also have a new Dinan lightened dual-mass flywheel and clutch to go in, but I was incredibly sick over Christmas and all that has been pushed back. The only other thing I can think of is a misfire, or the DME perceives a misfire, due to a worn out springing medium in the DMFW. The very high HP N54s are having a misfire at high load/high RPM possibly due to the dual-mass flywheel, so I am speculating that the DMFW may cause issues at lower RPMs/loads, too. I have 65k miles on mine now.

The one thing that cleared up my idle and low RPM hiccups most noticeably was cleaning the MAP sensors, especially the one in the intake manifold. They get oiled/carbon fouled. Also changing the pre-cat O2 sensors significantly reduced the hiccups, too.

Will BMW perform This Valve cleaning? and if so how will they determine that it need to be done?

I am also planning to install AR DP Cat-less this weekend...Will this affect anything?

Also is there a DIY for MAP sensor cleaning? My car has 38K on it now

[Jeff@TopGearSolutions]

Originally Posted by MSport35TT

Will BMW perform This Valve cleaning? and if so how will they determine that it need to be done?

I am also planning to install AR DP Cat-less this weekend...Will this affect anything?

Also is there a DIY for MAP sensor cleaning? My car has 38K on it now

More then 9/10 BMW does not warranty the valve cleaning but you can try and ask.

Catless downpipes won't have an effect on your idle if that is what you are referring to.

There is no "DIY Guide" to map sensor cleaning, but you simply remove it and clean it with Map sensor cleaner found at local auto parts stores. It's sensitive equipment so dont bend it or touch it, just spray it with the cleaner and re install.

[eric@helix]

Pardon me if you said this but how many miles do you have? if it's over 50k, you're due for a walnut shell blasting of your intakes.

[eric@helix]

Here's a link with info.

[hemi to e90]

Originally Posted by eric@helix

Pardon me if you said this but how many miles do you have? if it's over 50k, you're due for a walnut shell blasting of your intakes.

why is that linking to your intercooler?

[hemi to e90]

Originally Posted by eric@helix

Here's a link with info.

okay this makes more sense lol

[MSport35TT]

Originally Posted by eric@helix

Pardon me if you said this but how many miles do you have? if it's over 50k, you're due for a walnut shell blasting of your intakes.

38K miles...Cobb Tunned at 35K


The downpipe question was referring to the replacement of an o2 sensor that was a possible fix for the hiccup above

[volkswackin]

Check your ground wires for the coil harness...specifically check the crimps and solders..I've had more than one have a hiccup at idle with no faults and found the crimp and solder broken but still connected and just not making a good enough ground.

[MSport35TT]

Day 6 and they still can't figure it out. They are calling for a BMW field rep to come in see if he/she can fix this. Question, does the ecu tell how many times it has been reflashed and if so will it time stamp this? thanks.

[MSport35TT]

Bump

[BuraQ]

In your case what I would have done is ask BMW to falsh the DME with the latest software regardless if you have it or not.

They have a cause so I dont see what they wouldnt do it for you being that a known problem exist.

[MSport35TT]

Originally Posted by BuraQ

In your case what I would have done is ask BMW to falsh the DME with the latest software regardless if you have it or not.

They have a cause so I dont see what they wouldnt do it for you being that a known problem exist.

Will this affect a future performance tune? If i flash a Cobb or JB4 ?

[BuraQ]

Originally Posted by MSport35TT

Will this affect a future performance tune? If i flash a Cobb or JB4 ?

No, actually it should benefit the Cobb tune, and no the Cobb tune does not leave any image behind after reflashing back to stock.

I cannot speak for the JB4 as it is not a flashtune. I would recommend the Cobb AP though

[MSport35TT]

Originally Posted by BuraQ

No, actually it should benefit the Cobb tune, and no the Cobb tune does not leave any image behind after reflashing back to stock.

I cannot speak for the JB4 as it is not a flashtune. I would recommend the Cobb AP though

Cool, Thanks....I will let you know the turn out...For now I have the pleasure of driving a 2013 528i so I can't complain to much

[MSport35TT]

Day 11- So BMW called today and advised me that that based on "my recomendation" they have gone ahead and completed a Walnut blasting to the engine and car seems to be running a lot better. They are keeping him over night to do some more test and I should have him back before the weekend I hope. Since BMW is taking advice from me now, is there anything else they should be looking at or changing?

I don't think coil packs were changed nor MAP sensor clean (as posted above). Let me know what you guys think. Thank again

[MSport35TT]

Bump

[roadkillrob]

Since it sounds like BMW is now using you as the technician, you should either demand payment or recommend replacing your car with an M3!

[MSport35TT]

Originally Posted by roadkillrob

Since it sounds like BMW is now using you as the technician, you should either demand payment or recommend replacing your car with an M3!

LOL, right? Just looking for other items to check on before getting the car back.