Injectors as part of CBU cleaning?

Redsorcerer00 · 09-27-2021, 03:03 PM

Can anyone tell me if you have to clean injectors as part of a regular carbon cleaning on these engines?

Indy shop is trying to tell me that carbon cleaning will cost me $2,500 because injectors also have to be removed and sent out for cleaning?

Also if anyone in SoCal has any recommendations on Indy shops actually familiar with these, or recommendations for local help with alphabet delete I would be very grateful.

kbsilver · 09-27-2021, 06:38 PM

I had carbon cleaning once at 54K miles under warranty. I currently have 120K miles. Injectors have never been touched. I try to use top tier fuel and never used an additive.

While the injectors do not have to be cleaned, the intake manifold does. Often it's preferred to simply replace it (made of plastic) as the cost of cleaning is close to what it costs. 5 years ago the honest dealer cost of carbon cleaning and replacing the manifold was under $2K.

montr · 09-27-2021, 07:51 PM

As stated in previous post, for each cylinder, both intake and exhaust valve must be closed for doing the carbon cleaning. The injectors are not touched and do not need to be cleaned.

335dlci · 09-28-2021, 05:53 AM

Uhh I do.

lnxguy · 09-29-2021, 10:25 AM

Don't touch the injectors.

peteyypab · 10-07-2021, 07:15 PM

I would say it very much depends on mileage and your previous Fuel filter change interval...

If you have been changing the FF regularly and you're using quality diesel it probably is overkill anything less than 100k.

I bought at 43k, at 140k now and I've never touched them... I'm changing the fuel filter every 4th oil change, and I run 1/2 interval oil changes.

The original FF change interval was every other oil change fo those of us that remember

When its my turn to get out the walnuts I will be cleaning mine because I will be way over 150k im sure

Nadir Point · 10-15-2021, 09:18 AM

If it ain't broke, don't fix it. But (BIG but) in this particular case, the injectors are running just downstream of that same CBU situation coating the intake. If you have CBU, the injectors have probably seen better days. I would recommend REPLACING them if there's significant mileage on it.

Andystobbs · 10-17-2021, 03:33 AM

Quote:

Originally Posted by Nadir Point

If it ain't broke, don't fix it. But (BIG but) in this particular case, the injectors are running just downstream of that same CBU situation coating the intake. If you have CBU, the injectors have probably seen better days. I would recommend REPLACING them if there's significant mileage on it.

"just downstream"? The injectors are in the combustion chamber.

335dlci · 10-17-2021, 10:10 AM

I wouldn't replace injectors because of they have seen better days reasoning..

Nadir Point · 10-19-2021, 08:54 PM

Quote:

Originally Posted by Andystobbs

"just downstream"? The injectors are in the combustion chamber.

Ya think?

Andystobbs · 10-20-2021, 08:17 AM

I stumbled across the fact when searching for the exhaust back box which I replaced because it was just downstream of my dirty egr valve.

09-27-2021, 03:03 PM	#1
Redsorcerer00 Registered 0 Rep 4 Posts Drives: 335d bmw Join Date: Sep 2021 Location: Socal iTrader: (0)	Injectors as part of CBU cleaning? Can anyone tell me if you have to clean injectors as part of a regular carbon cleaning on these engines? Indy shop is trying to tell me that carbon cleaning will cost me $2,500 because injectors also have to be removed and sent out for cleaning? Also if anyone in SoCal has any recommendations on Indy shops actually familiar with these, or recommendations for local help with alphabet delete I would be very grateful.
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09-27-2021, 06:38 PM	#2
kbsilver Captain 143 Rep 631 Posts Drives: 340GT & '22 eDrive40 Join Date: Jan 2012 Location: North Jersey iTrader: (0)	I had carbon cleaning once at 54K miles under warranty. I currently have 120K miles. Injectors have never been touched. I try to use top tier fuel and never used an additive. While the injectors do not have to be cleaned, the intake manifold does. Often it's preferred to simply replace it (made of plastic) as the cost of cleaning is close to what it costs. 5 years ago the honest dealer cost of carbon cleaning and replacing the manifold was under $2K.
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09-27-2021, 07:51 PM	#3
montr Captain 192 Rep 768 Posts Drives: 2010 335d, 2018 430i G-Coupe Join Date: Sep 2009 Location: Atlanta, GA iTrader: (0)	As stated in previous post, for each cylinder, both intake and exhaust valve must be closed for doing the carbon cleaning. The injectors are not touched and do not need to be cleaned.
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09-28-2021, 05:53 AM	#4
335dlci Lieutenant Colonel 303 Rep 1,606 Posts Drives: 335d Join Date: Apr 2014 Location: Socal iTrader: (0)	Uhh I do.
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09-29-2021, 10:25 AM	#5
lnxguy Colonel 629 Rep 2,286 Posts Drives: 2018 540i xDrive. Join Date: Jun 2016 Location: Barrie iTrader: (1)	Don't touch the injectors. __________________ '09 335D '18 540i xDrive
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10-07-2021, 07:15 PM	#6
peteyypab Enlisted Member 8 Rep 40 Posts Drives: Just a few others Join Date: Oct 2014 Location: LeftCoast iTrader: (0)	I would say it very much depends on mileage and your previous Fuel filter change interval... If you have been changing the FF regularly and you're using quality diesel it probably is overkill anything less than 100k. I bought at 43k, at 140k now and I've never touched them... I'm changing the fuel filter every 4th oil change, and I run 1/2 interval oil changes. The original FF change interval was every other oil change fo those of us that remember When its my turn to get out the walnuts I will be cleaning mine because I will be way over 150k im sure __________________ Current Fleet:02 M5 Carbon Black - 11 335d M-Sport Alpine White - 08 Cooper S Pepper White - 07 Range Rover Supercharged Java Black The ones that got away:02 M3 Vert Jet Black - 04 A4 3.0 Quattro Brilliant Black - 77 Mercedes-Benz 300D Milan Brown Metallic - 02 Range Rover Java Black - 84 Mazda 626 Diesel
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10-15-2021, 09:18 AM	#7
Nadir Point Lieutenant 110 Rep 596 Posts Drives: Diesel Join Date: Dec 2015 Location: CO iTrader: (0)	If it ain't broke, don't fix it. But (BIG but) in this particular case, the injectors are running just downstream of that same CBU situation coating the intake. If you have CBU, the injectors have probably seen better days. I would recommend REPLACING them if there's significant mileage on it.
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10-17-2021, 10:10 AM	#9
335dlci Lieutenant Colonel 303 Rep 1,606 Posts Drives: 335d Join Date: Apr 2014 Location: Socal iTrader: (0)	I wouldn't replace injectors because of they have seen better days reasoning..
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10-20-2021, 08:17 AM	#11
Andystobbs Captain 197 Rep 720 Posts Drives: E91 Lci, Vectra B V6 Join Date: Sep 2019 Location: Chester, South Wirral iTrader: (0)	I stumbled across the fact when searching for the exhaust back box which I replaced because it was just downstream of my dirty egr valve.
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