When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I was reading many posts on the Audi R8 talk forum and saw some posts of concerns from members about carbon build-up in both the V8 and 10 engines. They did reference that a Direct Fuel Injected engine is very prone to this. I really don't hear that about this problem with Porsche engines. Am I missing something?
Every brand with a direct injected engine has these problems, The intakes valve doesn't get rinsed off by the fuel and this leads to carbon build up on the intake valve. If it gets bad enough it will cause misfires and other drivability issues. What's the fix you ask? Regular induction services. This service uses chemicals that wash the carbon off the intake valves.
The Audi 4.2 was notoriously bad with this. The R8 and RS4 are both known to have this problem where the intake valves need to be cleaned every 20-25K miles.
Every brand with a direct injected engine has these problems, The intakes valve doesn't get rinsed off by the fuel and this leads to carbon build up on the intake valve. If it gets bad enough it will cause misfires and other drivability issues. What's the fix you ask? Regular induction services. This service uses chemicals that wash the carbon off the intake valves.
If the manufacturers were filtering or trapping the crankcase fumes that are routed into the intake tract, there would be less carbonization of the intake valves of direct-injection engines. You can use a detergent like Seafoam, but the process is kind of scary - the engine stumbles and the exhaust looks almost as if the rings have failed (loads of white smoke). Alternatively, there is a walnut blast process that is performed when the engine experiences stumbling. Alternatively, it could be a service to be performed every 15,000 miles if you wanted to be proactive.
Our 9A1 motors have a squirter for the back side of the valve. Plus, the valve also rotates. Hence no abnormal carbon build up and no "dark side of the moon" effect.
There was a very good thread about this in the 997.2 Forum a few months back. I'll try to find it. Charles Navarro (L&N Engineering) also contributed.
I also use the Techron Fuel System Cleaner about 400 miles (one full tank of treated fuel) before every oil change as an added precaution.
...I also use the Techron Fuel System Cleaner about 400 miles (one full tank of treated fuel) before every oil change as an added precaution.
I’d like to try this before I bed down my Cab for the winter. I’ve tried to research the proper way to apply this product and found some folks apply it differently. How do you? Bring the fuel level down to < 1/4 tank, add the cleaner, drive 10+/- miles then fill up then drive until the tank is low, then oil change? Or do you simply add the cleaner while filling up, drive the 400+/- and oil change?
Every brand with a direct injected engine has these problems, The intakes valve doesn't get rinsed off by the fuel and this leads to carbon build up on the intake valve. If it gets bad enough it will cause misfires and other drivability issues. What's the fix you ask? Regular induction services. This service uses chemicals that wash the carbon off the intake valves.
Not true. See post #33 (and more good info in post #44) here:
Or do you simply add the cleaner while filling up, drive the 400+/- and oil change?
This.
About a week or two before I do this (will be making the call probably next week) I call and schedule my appointment with the dealership for an oil change.
About a week or two before I do this (will be making the call probably next week) I call and schedule my appointment with the dealership for an oil change.
I had a Mini Cooper S with DFI that was really bad with this. Twice I had to have the valves blasted with walnut shells to clean them. Yes, walnut shells. It's a thing.
If you do, then why is your post #2 false and misleading?
I'm not going to argue with you. Do your research. Google direct injected engine carbon build up. Pages and pages of very useful info. But you're right all that info is wrong and you're right. lolol Have a great day!
I'm not going to argue with you. Do your research. Google direct injected engine carbon build up. Pages and pages of very useful info. But you're right all that info is wrong and you're right. lolol Have a great day!
curious also, besides google can you provide some of your first hand experiences? Which manufacturer are you currently familiar with?
08-02-2018, 10:53 PM
CARBON build-up in engines
