Knock DURING Seafoam?
Knock DURING Seafoam? Just wondering what this could possibly mean, if anything.
My friend and I (he is a member here) seafoamed his car. Crankcase, fuel tank, and induction.
We put the seafoam in the brake booster just like the write up told us to do. Waiting 20 minutes and started her up and the seafoam did the job. However, right after start up after seafoaming he had a huge knock going on and it gave us a bad feeling. After revving it a little bit and having all the seafoam carbon build up clear up, it stopped knocking.
So before the seafoam, no knock. During there was a lot. After, none again.
What could this mean?
I have video of a portion of the seafoam we did. You can hear the knocking in the beginning when the engine idles a few times.
It is uploading now and will post when it is done.
My friend and I (he is a member here) seafoamed his car. Crankcase, fuel tank, and induction.
We put the seafoam in the brake booster just like the write up told us to do. Waiting 20 minutes and started her up and the seafoam did the job. However, right after start up after seafoaming he had a huge knock going on and it gave us a bad feeling. After revving it a little bit and having all the seafoam carbon build up clear up, it stopped knocking.
So before the seafoam, no knock. During there was a lot. After, none again.
What could this mean?
I have video of a portion of the seafoam we did. You can hear the knocking in the beginning when the engine idles a few times.
It is uploading now and will post when it is done.
My blazer knocked while I was adding the seafoam and then directly after. It cleared up and I chalked it up to the seafoam combusting after the fuel did. Like the seafoam in the cylinder fired when the valves were open. If it isn't knocking now I wouldn't worry about it.
yeah seafoam wil cause youre car to misfire depending at the rate it is put in. the knocking is most likely misfiring from the engine being overly rich. what i do is hold the rpms up and let it all just brn off and its back to normal. i would also recommend checking youre spark plugs for fouling. it will happen everyonce in a while when you use seafoam.
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seafoam this is something "normal" after doing a combustion chamber cleaning like this - could be carbon breaking loose and knocking around - back in the day you used to do this with a large glass of water- just pour it slowly down the carb,you dont want to hydrolock a cylinder- liquid dosent compress! can do bad things to connecting rods, bearings and generally ruin your week 
ive seen techs do this before 
ive seen techs do this before 
Anyway, read through that sticky in the General Maintenance section. Choco does an excellent job of explaining what SeaFoam is, an how to properly SeaFoam your car.
Yeah he does. We did everything by the book on how he said to do it, and so far so good.
I can imagine that the solvents first remove the oily dirt, then the water will remove the hard stuff...
What do you think about this combined treatement?
Yeah or when it backfires through the brake booster line, or you're leaning over the carb looking down it while pouring it in and it backfires all the smoke and seafoam in the intake into your eyes or when your car will not shut off. It's always fun to use.
While decarbonizing I noticed the fuel trims going -15%, this is the max those cars are able to do.
I can imagine that when restarting the PCM is still reducing fuel like hell and it takes a moment to get back to a normal situation. During this adaptation time the engine is probably running lean causing some knock.
After the cleaning I drove 20 miles on the highway at 60 mph in 4th (3000 rpm). at the beginning it knocked everytime I tried to accelerate.
A couple of days later I took a scan and was amazed to see that there is much less KR than before. Really much less
At WOT I used to have a couple of degrees, now it's 0 (zero)
I can imagine that when restarting the PCM is still reducing fuel like hell and it takes a moment to get back to a normal situation. During this adaptation time the engine is probably running lean causing some knock.
After the cleaning I drove 20 miles on the highway at 60 mph in 4th (3000 rpm). at the beginning it knocked everytime I tried to accelerate.
A couple of days later I took a scan and was amazed to see that there is much less KR than before. Really much less
At WOT I used to have a couple of degrees, now it's 0 (zero) 