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Seafoam in Gas Tank

14K views 80 replies 14 participants last post by  Mikey319 
#1 ·
Hi again, I've been reading about Seafoam and I can't find anything conclusive about JUST putting it in the gas tank only. I just filled it with premium (always 92 or 93 octane) and I used Lucas deep fuel clean about 3,000 miles ago, but I don't feel or see any difference. I watched YouTube videos and saw that it did little to nothing and then watched Seafoam videos and saw it worked very well. I want to use the Seafoam on my car, But I don't know if I need to change the oil after the tank of gas or not. I don't want to change the oil I just want it in the gas tank and that's it. Is that possible?


When it's time for my oil change I will be using it in there too but that's another 1,400 miles so I don't want to put it in until the day of, and then drive it a little with the Seafoam in and then get an oil change.
 
#57 ·
Wow.... I was a QUART low on transmission fluid.... Thanks Firestone thanks a lot for catching that.... NOT. The real award goes
To OTA. Thanks to them my car is shifting so much better. Still some hesitation when first being put into reverse and drive but it reduced a lot. I think once I start driving it with the added fluid it will go back to normal. They said it was a fine color and didn't need to be flushed like Firestone said.

Still don't know where my car is leaking air from because I got the code P0102 and P0420. But they haven't come back yet after they were cleared. OTA said get the car to them as soon as I can when the light comes back on so they can check it. He said he welded something but I didn't look.

I forgot to tell them about the power steering, but oh well. That can be saved for another day.
 
#58 ·
Looks like you have found a good honest shop to use for some of your service work. There will be some things that will be better done by a VW specialist. On the other hand Firestone is a place to have tires mounted and balanced, other than that they are just good at separating customers money from they're wallets.
 
#60 ·
Not necessarily a VW dealer, but someone who specializes in VW and or BMW repairs. There are a lot of indy shops that do great work. The VW dealer is not always a good bet.

Really anything engine related other than basic maintenance like an oil changes, brakes. Especially anything timing related.

You can always ask here before you have something done.
 
#62 ·
I tried SeaFoam in my tank once because I was lazy and i regretted it.
My tank inside must have been so bad that it destroyed my fuel pump. I don't know guys... it might have been a pure coincidence but the same day in the evening my car stopped in the middle of the highway and I found myself to be dealing with a dead fuel pump...

If you want to clean up your tank, I know it might sound a bit extreme, but the best way is to just demote it and wash it with gasoline. I mean put in a liter, shake a lot and dump it. Do it as many times you're going to have to until gas comes out clear. You will see how much crap will come out... Professionals say that if you wan't to keep your tank well maintained this type of clean-up should be done once every 10 years.
 
#65 ·
I wouldn't recommend using sea foam in your gas tank. On one of Chris's Utube videos I recommended that he should test out the redline S1 fuel system cleaner. And low and behold someone read my comment and sent him a bottle of it. It's supposed to be good stuff. I believe one bottle is strong enough to treat 100 gallons of gas and it's safe for continuous use. I would give that stuff a try as it is more consentrated than almost any fuel system cleaner on the market.
 
#69 ·
To my knowledge, you can't change it. It's built that way on purpose.
 
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#71 ·
It would be interesting to test a placebo cleaner, like add "NOTHING" to the gas tank/engine and then drive the car hard... I bet it has the same results as the ones in the videos above :) And my cleaner is much cheaper.
Sorry guys, I am very skeptical... I believe that not all gas is created equal, and some might have better/more cleaners than others, but I don't feel anything you use one time will yield tremendous results.
BTW, the newer Passat with direct injection has lots of carbon deposits problems, and VW "recommends" using a top tier gas. Is it really a good solution?
 
#73 ·
P0491 and P0492. Those are new. And another question....Does it look like my front fender was not bolted tight enough after Firestone had it apart? It looks that way to me. First day I got the car. It was untouched in original condition and here it is after Firestone took it off and put it back together. Also after I cleaned it :lol:
 
#74 ·
P0491 & P0492 these are not really a big deal. The next time you have service done you can have it checked out. Could just be the hose from the SAP is not connected, or it could be the pump has gone bad. If it is the pump the Combi valves may also be bad or at least need to be cleaned. This will not affect the engine or make it run badly. If it is the pump you will want to find a used one at a junk yard that works for a replacement. It will be good for you to go get one off of a parts car as it will give you some experience and you will know hoe to install it on your on car. This way you get to practice on the the parts cars!

Possible Causes

Fuse or relay for Secondary Air Injection Pump faulty
Hose(s)/Piping between Secondary Air Injection Pump and Combi (Secondary Air Injection) Valve leaking
Secondary Air Injection Solenoid(s) faulty
Secondary Air Injection Pressure Sensor faulty
Combi Valve(s) faulty
Secondary Air Injection ports in the cylinder head(s) plugged with carbon See Special Notes

Possible Solutions

Check fuse and relay for Secondary Air Injection Pump system.
Check hose(s)/Piping between Secondary Air Injection Pump and Combi Valve
Check Secondary Air Injection Solenoid(s)
Check Secondary Air Injection Pressure Sensor
Check Combi Valve(s)
Clean Secondary Air Injection ports in the cylinder head(s) if obstructed with carbon See Special Notes


The Bumper cover looks fine.
 
#77 ·
Yes, if the hose is disconnected you would hear that. I would say since you recently had the timing belt done that they disconnected the hose and did not re-connect it when they finished the job. You can check it yourself without removing the bumper cover. And you can see the pump from under the car with the belly pan / skid plate removed.

Ratchets has a lot of good videos.
 
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