Quick Seafoam Question

Be ready for half the responses to be positive on using it and half to be negative. Personally I have used it once or twice in the past on beater vehicles with no negative results.....maybe a slight increase in gas mileage but modulating your right foot would probably give the same slight increase of MPG as well......I know keeping my foot in the carpet sure decreases MPG. I would wait for the alcohol. If you do decide to use some unplug the mass air flow sensor, unclamp the hose to the intake pipe, turn it 180 degrees and slowly feed it through the pipe......there are other ways but that is probably the easiest. I would go with the spray version that has the straw....not too keen on pouring liquid straight down into an intake. Just a thought....good luck with your mods.
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Here's my personal experience:

My parents 96 explorer with 250,000 miles had a check engine light for a bad cat and would not pass state emissions. Reset the pcm and the light would come back on within a few minutes of driving. Used sea foam, reset pcm, light stayed off for about a month and passed emissions. Mom said the car ran much better and had more pep.

2000 focus with 100k miles, ran and idled poorly. Sea foamed it after cleaning the maf and a few other sensors. Idled great and over all ran better.

A friend's ls1 corvette with 90k, sea foamed it and made no difference. Ran great before and great afterwards, made just about no smoke during the process.

94 z28 with supercharged 383 and oil consumption problem. Sea foamed and smoked like a chimney, ran great aftewards.

There are others but you get the idea. If you have carbon buildups, that stuff eats it. I've never seen negative effects from sea foam and have used it on many vehicles. I've also only used the bottled version through the brake booster vac line, not the spray.

On a side note I've used water as well. 78 el Camino ss, set choke and left to high idle for 15 minutes. Once hot I slowly poured about half a quart of tap water in the carb. Afterwards running temps were cooler, mileage went up, as well as idle quality and power. That was before I found out about sea foam.
The water trick has been around for a long time. You should probably use demineralized water though.

I've used Seafoam poured into the fuel tank on a few motorcycles. Works well in that application.
Bought a bottle of Seafoam yesterday. I plan on putting it in my Regal T's gas tank tomorrow. No matter what I do, I can't get that car to idle.
I've used it before in my beater pickup. Idk if it did anything for it but it was fun. Used it in my fuel tank a few times. Idk if it helped anything but it made me feel complete. I have half a bottle left, going to use it tomorrow Noe that I've read this post. Forgot about it lol
Sea Foam is great for anything , Read the bottle for directions . I have used it for bout 15 years . When I got my GN last Sept I ran 2 bottles thru the gas tank over a few fill ups then changed the fuel filter . Its really good stuff
I've found not much happens when putting it in the gas tank vs directly into a running engine. Your results may vary of course but I've found it to work better using the following procedure.

The procedure I have used is to start off with a hot engine. Pull off a large vacuum source like a brake booster line, have someone start the engine with a thumb covering the open line. Slowly open up the vacuum leak and pour in the juice, more and more till the engine stalls/runs terrible and tell the other person to cut the ignition. Leave the engine off for 5 or 10 minutes, then start for round 2. 5 or 10 minutes off, then start and drive.

This will allow the juice to coat everything and eat up the bad stuff. When you burn it it will take the buildups with it. The more smoke produced while driving, the more junk going out with the sea foam. If no or little smoke is being produced, then things were clean to begin with.

The main thing it will clean using this process are combustion chambers, piston tops, exhaust valves, and cats of you have them.