Hello, I was wondering if this every happened to anyone.

I was Seafoaming my car through the brake booster and then when I shut the car off, the engine kept going. And there was a horrible knock while it was running by itself with the key removed.

And so I ran over and plugged the brake booster hose and it stopped.

This has never happened to me and I have always used the same procedure. Ever since I got the car, but this time it for some reason kept running by itself, I haven't started my car yet. Since right after that happened I ran a google search and found nothing. So I came here.

I also did not stall the car or anything with the Seafoam, I let only a tiny amount in at a time and nothing changed in the way I did it this time verses the other times.

 

Okay after I've calmed down a bit it seems like it was probably the seafoam burning off or something simple like that and the open vacuum line probably let it run.

But it sure scared me good when it went BANG BANG BANG when I turned the engine off.

 

That would be enough to scare the crap right out of me.

 

Nah! Its fine. Just go start it up and watch it SMOKE.

 

Happened to my Max I think around twice out of 6 times I have Seafoamed it. I was like 'wtf...' too when it happened the first time.

 

Thanks for the reply guys, so I started the car up and everything was normal no problems.

I was extremely worried about the knock damaging the engine but so far all seems good, PHEW!

 

samething happened when we did my friends mazda 6

 

It's just the SeaFoam burning up. No biggie.

 

Snake oil... Just sayin... Engine knock, or run on (dieseling) isn't good for a gas motor.

Sea Foam + Smoke = Marketing 101 - It's working, yea right!

 

my car is running better after a treatment
smoother accel, smoother idle, seems to be getting better gas mileage (still going through the first tank, so jury is still out on mpg).

but I agree, dieseling is not good for a gas engine.
my suspicion is some carbon got hot, and continued to ignite. shutting off the engine cuts the spark/fuel system, so it won't do that.

 

Yeah the odd thing was that I ran Seafoam a few weeks before and it "should" have cleaned things out. But I decided to run it one more time, just to really make sure.

But that is why I really panicked when it happened because I knew what engine knock and all that could do to an engine. Thank goodness I ran over and stopped it instead of trying to rev it

 

Sea Foam does work. I've used it before, and I definitely felt an improvement in motor performance. It also helped get rid of that irritating Nissan pinging that our car does under load.

A few things to remember about Sea Foam, though:

1) It can burn up spark plugs. Make sure you replace your plugs shortly after Sea Foaming. Or at least check them to make sure they're still in good condition.

2) It can clog up cats. If you're going to do Sea Foam several times, make sure you unbolt your cats.

3) It can strip the factory coating off of the valves/cylinders if done too many times. I wouldn't run Sea Foam through the brake booster more than once a year at most.

 

Wow that is a lot more than what the bottle says to do!

But yeah I think after this time I am going to wait a lot long between uses and be more careful, next time.

I guess more really isn't better except when it comes to hookers

 

I tried it once just to see what all the hype was about and I still think its just a placebo effect. I did see lots of smoke and I guess thats the whole wow factor, but afterwards I never felt any sort of difference. I wonder if anyone has ever done scientific experiments to prove that it increases power or "smoothness".

 

...

 

The whole "smoke means it's working" argument would stand if I hadn't noticed this my first and second time using Seafoam:

The first time I used Seafoam, my car smoked like a banshee. Literally smoked out the whole neighborhood, and smelled absolutely fowl.

The second time, however (about 8 months later), there was a little smoke, obviously, but not nearly the amount that there was the first time the car ever underwent the treatment.

This leads me to believe that the Seafoam is indeed doing...something. What? I'm not totally sure. Let's just say that I hope it really is benefitting my car in the long run.

 

I have a spark plug that is caked in carbon I should dip that in Seafoam and see what it does.