I did this a while back on my 318 with 136k miles. It seemed to smooth up the idle, but I don't know how much of this is a placebo effect. It didn't make any huge differences, I think I still need to change my O2 sensor.
The bigger difference in the operation of my car was replacing the thermostat. That made for a 10% improvement in economy as it was running cool (hence rich) all the time (especially in winter).
I think the sea foam will help if you have been running rich for some time, but make sure you fix whatever was causing it to run rich first or you won't do any long term good.
Doing lots of internet research on this subject I found that it is something many mechanics do to help older cars. They often use water or ATF instead of sea foam to suck through the intake. I will stick to sea foam as I know it is safe. I think it is highly unlikey to damage something using this technique as long as you don't suck so much fluid that you cause hydrolock. Overall it is a fairly safe procedure. |