So I ordered an Alky kit for my new (to me) 38k mile SHO. I've notice that idle can be just a hair rough when cold. And I know that the back of these valves can get caked with unburnt fuel, causing a rougher idle. I'm wondering if the use of meth will eventually clean the back of lo of these valves. Anyone know of any evidence that meth has made any difference in reversing the accumulation?
It all depends on the severity of the issue!! The Hair line rough idle you claim is normal on this platform. AFAIK. Z
To gauge the severity of the problem, I would look at the inside of the intercooler/CAC. If it is dry or has barely any accumulation of crud, more than likely the backs of the intake valves are doing good also. Not sure how strong of a solvent methanol is.
Fun "old" read btw
http://www.hotrod.com/articles/ctrp-0702-alcohol-engine-maintenance/ (http://www.hotrod.com/articles/ctrp-0702-alcohol-engine-maintenance/)
https://www.hemmings.com/magazine/mus/2008/01/The-Lost-Art-of-Chemical-Carbon-Removal/1567737.html (https://www.hemmings.com/magazine/mus/2008/01/The-Lost-Art-of-Chemical-Carbon-Removal/1567737.html)
http://www.oilem.com/turbo-fuel-stratified-injection-tfsi-direct-port-injection-carbon-build-up-problem/#comment-1842 (http://www.oilem.com/turbo-fuel-stratified-injection-tfsi-direct-port-injection-carbon-build-up-problem/#comment-1842)
"Forced induction DI engines are the easiest to treat as the carbon is generally softer and lower in volume when compared to NA DI engines, where the carbon build-up is usually much greater in volume and harder. This is because the build-up in NA engines usually has much more oil lube contamination making it much more difficult to remove. The Audi RS4 engine springs to mind."
Thanks for the info. Ill see what LMS has to say