I haven't gotten any smoke since the first treatment a couple years ago. I just added seafoam last weekend, no smoke but I could smell the fume in the exhaust. I'm considering pulling the IAC & throttle body to check for build up... My thought is that there shouldn't be much build up if the seafoam is getting fed through the intake properly.
Maybe feeding the seafoam into the brake booster line or throttle body will cause more smoke?![]()