Discussion Starter · #1 ·
My caddy has about 75,000 miles on it i occasianally floor it and beat on it so to speak. I was readint that the northstar engines have problems with carbon deposits in the combustion chamber causing a "cold knock". I have heard you should use TEC by general motors to get rid of them, put it in the pcv valve let it soak overnight and floor it all out. it sounds like a good idea but i dont want to change the spark plugs again. i also heard that if you just drive it hard a couple of times this will get rid of the deposits just fine too. what should i do. has any one used this product how does it work.