alansd

seen a lot of info about the carbon build problem.Can this be prevented? maybe running Techron or something. Also maybe winding the motor up higher rpm range?Just wondering Im bigg on prevention....

Vegas-roadster

The best preventive is using Top Tier gas. A study by AAA showed 90% reduction in carbon deposits on cars using Top Tier. The value of occasional use of additives is minimal. Someone did a study of the various cleaners and the info is out there somewhere on the web. He did SeaFoam, Techron, etc and the effect on carbon build-up on cylinder heads was minimal. He had the best results by adding generic toluene. That said, I'm an old school guy that throws in a can of Techron every 6-12 months. I've tried other brands but they sometimes result in a CEL.

alansd

i saw that additive review, figures. even marvel mystery oil did badly. Ive used that for 50 years, seemed like it worked. oh well.
top tier; bp, chevron, exxonmobil, shell,amoco?porsche recommend techron,so it cant be all bad,, i guess.

porttac

Nope. The gas never touches the back sides of the valves..direct injection engines have this problem..and all I have heard from Audi is " drive it like a race car" and burn the carbon out.

Just had a friend have Audi clean the carbon out of the back sides of the valves..coat him $1400.

porttac

https://audiclubna.org/north-atlanti...ld-up-removal/