Have used seafoam for both the Lexus. Just fine.

 

Use it in my Tacoma, wife's Sienna and JD lawnmower. JD is where its noticeable. Good but pricey

 

Used Sea Foam on my 92 sc300 with 208,000 miles and it was a nightmare. I followed instructions and 2 weekes later I had 2 clogged injectors and piston rings went out in 2 cylinders. Now is this a coincidence or what? Because the car ran wonderful before I used that stuff!
In my opinion sea foam is a murderer!

 

I did a Sea Foam treatment through the pcv line. You know, run the motor and let it suck the fluid through. What stinks is with this electronic throttle you cant bring up the rpm unless you have a helper. Any way, it started the smoking out the tailpipe stuff which was fine. Then I go to shut the engine off and it was pre ignitioning big time!! So I would turn the key back on, it would resume running, turn the key off Dieseling big time again! Finally I put it in drive and it very reluctingly died. this scared the Hell outta me! I thoght it was going to destroy the damn thing! So I restarted and went for a ride. All has been well since. When I did this to my 01 RX I got multiple miss fire codes. So amybe this stuff isnt really a good idea to use this way. Although I have a feeling this motor was carboned up, so this would explain the Dieseling.

 

^If she is super gummed up, it will need to be done more often for a few oil changes.

I did it once, the thing barely smoked when i did it. Never bothered with it again, i just run some injector cleaner once in a while, since it burns some of the carbon off itself anyways.

There was/is a few members in the ES300 boards that do this once every 3mos or so, for years without issues... so i think its coincidence in some of these cases.

 

If she is super gummed up, it will need to be done more often for a few oil changes.

I did it once, the thing barely smoked when i did it. Never bothered with it again, i just run some injector cleaner once in a while, since it burns some of the carbon off itself anyways.

There was/is a few members in the ES300 boards that do this once every 3mos or so, for years without issues... so i think its coincidence in some of these cases.




I agree my motor was/maybe still is carboned up. When I got it 2 1/2 years ago, it was owned by a woman near Phily. I know she used Regular fuel because the tail pipe was really carboned up bad. And it was serviced at my dealer in Doylestown on average of 5-6,000 miles on their bulk oil. The dipstick had a coat of varnish on it, unfortunately you cant see in the oil fill hole due to that stupid baffle. The 3.5 Liter motors dont have a baffle like this, I seriously thought about removing it. What possible service does it have being there?

 

came across this thread because heard the same thing. i have a 08GS350. 66k miles. fuel injectors went bad replaced for 2k. now engine code cat below threshold. dealer says 4k for new cat and long pipe. saw videos of seafoam being able to clean cars by pouring down the intake. any thoughts or advice how to fix cat? cant pass emissions.