2008 535i, 70K miles, JuiceBox 3. Normally run on Map 0, but sometimes I click in Map 2.
Over the last month or two, sticky carbon gunk has been accumulating on the exhaust tip, mpg has dropped a bit -- about 1 mpg.

I thought it was running rich, needed adjustment.
Service tech at BMW recommends de-carbonizing the head - $530.00

Anyone have experience with this service?
Will it address the issue?

Errowen

 

Unless you're forced to daily drives in sluggish city life I'd (1) skip the de-carbonizing sales pitch, (2) get out on the highway once a week and treat it to a run up through the gears and a 75mph cruise, (3) be sure to feed the beast a steady diet of Tier I Premium gasoline and (4) an occasional drink of Chevron Techron Fuel System cleaner.

 

"de-carbonizing the head - $530.00"

Sounds pretty cheap to me. What does it entail? (Must be some sort of pressurized system with the head remaining intact - probably a BG related product offering).

Removal and cleaning of a head will certainly cost a lot more than $530 bucks.

Run some BG 44K or Chevron through it. Also use BG "Engine Purge" prior to your next oil change. Very effective at removing carbon deposits with these products.

A caution on BG "Engine Purge" as it will remove a lot of built-up crap in your engine and could possibly clog your oil ports. But at 77K miles, this shouldn't be an issue unless the previous owner simply decided to not change the oil - ever!

 

From the posts that I have read, the 535 eventually will need this. I guess it's just at what point do you feel that it does... I've also read good reports from feedback after the cleaning was performed. I believe there was one write-up I ran across that said it did not help, but when I read further into it, there was an issue with the car and they were hoping the cleaning would eliminate it. With the direct injection it sounds like the task is inevitable.

There is a nice DIY on this forum for those who are mechanically incline and wish to take on the task. But if that’s what the going rate is, I believe I would have someone who has done it before do it. You only have to remove the intake not the head and then plug up the ports so that all the media doesn't get into the head where is can't be removed.
There is a nice DIY on this forum for those who are mechanially incline and wish to take on the task. But if thats what the going rate is, I belive I would have someone who has done it before do it. You only have to remove the intake not the head and then plug up the ports so that all the media doesn't get into the head where is can't be removed.

 

Assuming you are talking about the walnut shell cleaning, the answer is yes. I had this done on my 535i (sold it for other reasons) and it was night and day. No more rough idle in the AM or when temps were below 50 degrees. No more hesitation during spirited acceleration. I paid $400.

 

Shop around.

 

Thanks all for the suggestions and explanations - you guys are terrific. I'll get the process done.
Errowen