MangoMan

I just recently dropped a can of seafoam in my car and now it idles at 750 as it should and runs fine no stalling or such but it is not nearly as smooth as it was before I put that SeaFoam in my tank. It is now slightly shaking the steering wheel. I was thinking it was the air filter and changed it but didn't help. I am now thinking that the seafoam loosened some junk and clogged my fuel filter slightly and is now starving the engine causing a slight vibration at idle. Does this make sense? If the car is idleing fine but a little rough what could it be? 140,000 miles on a new Lexus dealer rebuilt motor, new timing belt, oil pump and water pump and the engine looks clean.
Thanks for all your help in the past!

swifty562

where exactly did u drop the seafoam... engine?...gas tank....vacum hose? all?

Pheonix

I would doubt it going in the gas tank.
The concentrations of any gas tank addative are so minute. My arguement has always been they don't really do anything. Let's face it, if anything you could put in a bottle. Gasoline is already a pretty harsh solvent.


Did you change the air filter at the same time? Most of the time, rough idles are caused by a dirty idle valve, or misfires/poor combustion. Which is usually nothing more than a vacuum leak, or a spark plug being playful.

MangoMan

Does anyone have a picture of where the idle valve is on a 99 ES 300?

smokesgtp

I'm guessin it went in the tank. Most lexus owners are not gonna go pulling off their brake booster hose or let alone visiting a parts store that sells seafoam lol. I wouldn't put it in the oil though no matter what the bottle says. You probably just fouled a plug, large pieces of carbon can cause problems if you have never used it before on an engine with 140k. I used it on my old grand prix with 138k in the vaccuum line and it put out enough smoke to pull the neighboors out of their homes, along with fouling a plug. Same symptoms. Have you driven it?

MangoMan

Yes I have driven it and it feels like a fouled plug now that I think about it! I need to check that right away!