I'm looking for opinions on BG direct injection service. The car in question is a 2011 BMW X5 xDrive35i with over 100k miles. The dealer is recommending this service to clean the intake valves since it has direct injection at a cost of $270. At this mileage, there's bound to be some carbon build-up on the intake valves, no? Has anyone here ever bought this service? Would you recommend having it done or not?
BG direct injection service. Opinions?
- Thread starter racerviii
- Start date
Have you noticed any degradation in performance that would necessitate such a treatment?
I have not. I know this is a service department upsell but without visually inspecting the valves, how would one know if there is or isn't carbon build-up? Would you wait until there is a degradation in performance first? Or would you have it done as preventative maintenance?
BG brought their machine by a few years back when I worked at VW and a customer in for a cleaning (MIL on, cold-start misfires) let us use his car as a demo.
The BG service didn't even touch the deposits.
The BG service didn't even touch the deposits.
My opinion is that this is another solution in search of a problem. If you had confirmed deposits or if you noticed performance degradation, then that would be another thing.
Here it seems to be a service center upsell only.
If it has enough power for how you drive it, then if it were mine I would not do it.
Years ago I use to fly remote control model airplanes quite often. After the first couple of years I got good at it and no longer crashed them. And I flew them for may years and many many times. I had hundreds, and maybe even thousands of hours flying them, and one problem I ran into was an engine that had carbon build-up in the cylinder above the piston. I used some solvent to loosen the carbon and it came loose and the piston scratched the cylinder wall very bad with the carbon before it blew out the exhaust. That engine ran good enough to still use when the carbon was in it, but it could not produce enough power and did not run right after the cylinder was scratched. So by trying to clean it and get more life out of it, I ended up ruining it instead. Carbon can exist in very abrasive particles. Sure in some forms it may appear as being brittle or even soft such as soot. But Carbon is also use as an abrasive. A common abrasive is made of carbon paired with silicon, it is called carborundum.
So you should consider that when you do one of those cleanings with the engine running that carbon does get into the cylinder, and in the brief time it is in the cylinder some if it probably will get trapped in the area at the edge where the piston meats the cylinder and then be dragged upward while the piston moves up. Weather this causes significant damage to your engine is a crap-shoot. Sure there is a good chance it will be blown out the exhaust and not stay in the cylinder long enough in a spot that causes damage. But there is a chance that a sharp abrasive particle of it gets in the spot where the piston drags it up against the cylinder and damages it enough to cause enough loss of compression to damage the engine to the point that it no longer runs proper.
So, if it ain't broke don't fix it. If it produces enough power for what you need from it, then leaving it as it is is the safer option.
Again, if it were mine, and it produced enough power for how I used it, then I would not do that type of cleaning of the intake valves, even if it were offered for free, strictly because there is the very real chance that a cylinder wall can be damaged by carbon particles that came loose because of that type of cleaning.
Years ago I use to fly remote control model airplanes quite often. After the first couple of years I got good at it and no longer crashed them. And I flew them for may years and many many times. I had hundreds, and maybe even thousands of hours flying them, and one problem I ran into was an engine that had carbon build-up in the cylinder above the piston. I used some solvent to loosen the carbon and it came loose and the piston scratched the cylinder wall very bad with the carbon before it blew out the exhaust. That engine ran good enough to still use when the carbon was in it, but it could not produce enough power and did not run right after the cylinder was scratched. So by trying to clean it and get more life out of it, I ended up ruining it instead. Carbon can exist in very abrasive particles. Sure in some forms it may appear as being brittle or even soft such as soot. But Carbon is also use as an abrasive. A common abrasive is made of carbon paired with silicon, it is called carborundum.
So you should consider that when you do one of those cleanings with the engine running that carbon does get into the cylinder, and in the brief time it is in the cylinder some if it probably will get trapped in the area at the edge where the piston meats the cylinder and then be dragged upward while the piston moves up. Weather this causes significant damage to your engine is a crap-shoot. Sure there is a good chance it will be blown out the exhaust and not stay in the cylinder long enough in a spot that causes damage. But there is a chance that a sharp abrasive particle of it gets in the spot where the piston drags it up against the cylinder and damages it enough to cause enough loss of compression to damage the engine to the point that it no longer runs proper.
So, if it ain't broke don't fix it. If it produces enough power for what you need from it, then leaving it as it is is the safer option.
Again, if it were mine, and it produced enough power for how I used it, then I would not do that type of cleaning of the intake valves, even if it were offered for free, strictly because there is the very real chance that a cylinder wall can be damaged by carbon particles that came loose because of that type of cleaning.
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BG makes some very good products (BG-44K).
What would walnut shell cleaning vs the BG? If mine was bad , i'd go the walnut cleaning route.
A money maker for service departments and service writers. Probably not worth it.
Mechanical cleaning is the only way to remove CBU. Walnut blasting, picking, and scraping.
As a bonus, the exhaust smells amazing when you first start it up after.
Walnut blasting dyno results
I work at a tuning company and also do some specialist things like DSG diagnosis/repairs, DPF cleaning( not the cheap way but the good way ), DPF removals, tranny flushes and intake cleaning. Wanted to share this walnut blasting cleaning with you guys. I'ts my dads car, recently bought. '08...
bobistheoilguy.com
Just because you don't notice and there is no CEL/MIL does not mean there is no degredation of performance.
Like the boiling frog, you do not notice incremental changes.
well I disagree. Will he not notice 5%....maybe, but who cares.
4WD
$50 site donor 2024
Seems you’d have to start this early in the life of an engine and then do it often. Can’t be cost effective …
There are some using vacuum lines and aerosol cans - but again - that’s not for waiting 100k and dealing with baked on CBU … A few threads mentioned Noack and SAPS as preventative ?
There are some using vacuum lines and aerosol cans - but again - that’s not for waiting 100k and dealing with baked on CBU … A few threads mentioned Noack and SAPS as preventative ?
It would be gradual and not noticed necessarily.
The "induction" service is the spray cleaner through the throttle body
BG's GDI service is very labor intensive. It's a 2 part chemical cleaning system which they use a bunch of zip ties bunched together to act as a scrub brush. So, yes the dealership has to remove the intake manifold to do this.
BG's GDI service is very labor intensive. It's a 2 part chemical cleaning system which they use a bunch of zip ties bunched together to act as a scrub brush. So, yes the dealership has to remove the intake manifold to do this.
In my opinion the chemical cleaners are really best at prevention when used on a regular basis. Once the valves are covered in the mess at 100k - a chemical cleaner isn't gonna do much except wash off the most recent gunk while the old gunk stays behind baked on. Only manual cleaning is going to fix that and that requires removing the intake etc and getting to it. I have an 08 CTS with the 3.6Di and 190k miles. Just prior to every oil change I spray a can of intake or carb cleaner thru the intake. I had to replace the injectors at the 175k mark and while in there I was pleasantly surprised at the valves. They were not perfect but they had minimal buildup so my routine proved to be worth the effort.