Decided to Seafoam my '08 MCS with 92K miles. I slowly poured approximately 1/3 of a can down the PCV hose with the warm engine running then shut the engine off for about 15 minutes.

Here's what's very odd. I started the car and a puff of white smoke came out the exhaust… which of course is expected. Except after about 2 seconds the smoked ceased. That's it! I ran/drove the car for about 30 miles thereafter and not a whiff of smoke. What gives? Was my engine clean? I don't get it. Any ideas?

Ian

 

I have no answers .. but I did want to mention that when I did this with my 07 MCS about 3 months ago with 56k, it did the same thing! Smoke for 2 seconds and that was it. I mean, no complaints, but certainly not as bad as I was expecting.

 

smoke doesnt billow out unless you rev the hell out of the engine or unless it is extremely dirty.

 

Yeah you really have to rev it to get it to smoke. I did mine along with a couple other cars at the same time. Mine smoked the most another smoked a bit and the third one hardly smoked at all.