[dbs600]

When the weather turns cool, my car doesn’t run as smooth.

Slight rumbling here and there, which was experienced in the past as well.

Occurs when changing between park, drive and reverse and when idling; all intermittent.

Acceleration doesn’t seem as smooth at times either.

Not present when warm out.

Definitely complained of same under warranty, but fell on deaf ears.

Any thoughts?

Thanks.

[Mbbrewer]

Sounds like the same issue I had. The valves had a bunch of carbon build up due to the direct injection. They had to drop the motor and walnut blast to clean it. Engine ran great for 3 weeks and now the rough idle is back.

[550Reasons]

a redline a day keeps the carbon away

[Mbbrewer]

Originally Posted by 550Reasons

a redline a day keeps the carbon away

Unfortunately that's not been the case for me.

[dbs600]

Thanks, Gentlemen.

What are we going to do about this, Mbbrewer?

Were you under warranty? Factory or extended?

Blasting covered under same? If not, how much was it?

Did you have a dealer or an independent perform the work?

Crazy how quickly it's come back for you!

Sounds like arterial plaque build-up. :|

[Mbbrewer]

Responses below...

Originally Posted by dbs600

Thanks, Gentlemen.

What are we going to do about this, Mbbrewer? There's not much you can do about carbon buildup with DI. Fuel detergents Do not touch that side of the valves to keep them clean. Only way to clean the carbon is to pull the motor and walnut blast away. Personally, I'm going to dump this car when my warranty is up. N63 is going to be a nightmare.

Were you under warranty? Factory or extended? 3 years into factory warranty

Blasting covered under same? If not, how much was it? Yes it was covered

Did you have a dealer or an independent perform the work? Dealer

Crazy how quickly it's come back for you! Agreed and I'm not happy about it.

Sounds like arterial plaque build-up. True Statement :|

[dbs600]

Originally Posted by Mbbrewer

Responses below...

Wow; thanks for the sad detail.

I'm confused; would've never gone DI.

I keep forever; seems longevity of these is not.

What's the point of DI, more power, better fuel economy?

Seems that power and fuel economy will only decrease in time!

[rogueshot]

i keep hearing that walnut blasting is "never" covered under warranty....rough idle and rough starting/acceleration is a pretty common complaint among N63 owners. Mine smoothed out almost completely following CCP, software update and ignition coil replacement. Apparently an ignition coil "going bad" intermittently has been an issue for quite a few folks.

I still suspect that carbon build up on the intake valves is contributing but dealer wont goodwill the blasting and I am not paying their bloated price for it....I am looking at having a reputable indy to do it (Crofton, MD).