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Vacuum line Seafoam question


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We did ours a few weeks ago and went through the Throttle body as recommended by others. You get the benefit of it being cleaned as well the sensors; although, it does require a little more dis-assembly. Seafoam now sells it in spray form and this was super easy to regulate. Car runs great! My neighbor was so impressed we did his Honda a week later. Using the Seafoam through the intake also has the unrelated benefit of showing potential leaks within intake/exhaust system, which mine didn't have, but the Honda did.

Search my posts under Seafoam and listed will be the valuable opinions of others.

John

Edited by john40iowa
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I always pull the brake booster hose and suck into that hose going directly into the intake manifold while engine running, pouring/sucking slowly for like 10 seconds then have your assistant kill the ignition IMMEDIATELY when you tell them then, (let engine sit for 10-15 minutes), re-start engine use the throttle and watch the smoke show! Rinse and repeat like 3 times.

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Sorry, I thought you guys were professionals

 

I'll go ask over at a Toyota forum

 

:brow:

 

a lot of us are pros. ever heard of a search function? use it. dont be insulting in here, and btw the yota guys wont take that crap either. if you need an answer that bad then go pay a pro to do it for you. otherwise use your keyboard and brain and figure it out. cmon, your thread isnt the only one on this subject so i know you can find one. this is the best soob forum ive ever seen. we're so helpful in fact that at times we can even help you help yourself. use the brake booster line. or one of the many other responses. good luck, hope it works RV

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a lot of us are pros. ever heard of a search function? use it. dont be insulting in here, and btw the yota guys wont take that crap either. if you need an answer that bad then go pay a pro to do it for you. otherwise use your keyboard and brain and figure it out. cmon, your thread isnt the only one on this subject so i know you can find one. this is the best soob forum ive ever seen. we're so helpful in fact that at times we can even help you help yourself. use the brake booster line. or one of the many other responses. good luck, hope it works RV

 

It was a joke, don't get your panties in a bundle.

 

I've read not to use the brake booster line. My question was is the one used in the video above an okay one to use.

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  • 1 month later...

A little old, but figured I'd post anyway.

 

Seafoam is good stuff; I use it in all of my cars (when I'm not overseas; it's generally not available there). There's usually a very noticeable before vs. after with it.

Now, nearly all of my cars have been at least 15 years old when I acquired them, so they had about that many years' worth of build-up in the intake system (maintenance seems to not be something most people get). On Subarus, apparently build-up in the intake valves is a problem, because there's an OE product similar to Seafoam (called something like Subaru Upper Engine Cleaner) designed especially to do this cleaning.

 

Anyway, when I first started using the stuff, my cars were either carb'd or MAP-based EFI, so I could easily dump the stuff straight into the throttle. When I first tried on a FI Subaru, I couldn't get the engine to run with the main air hose disconnected from the throttle body, so I tried using vacuum lines: it didn't work very well, as most of it kind of leaked out or just pooled up.

Later, I discovered that the problem was that 'Rus generally use MAF sensors, and that with no air flow signal from the MAF while the engine is running, the engine would stall.

The solution: disconnect the MAF sensor (the CEL illuminates, ECU approximates air intake using O2 sensor and/or engine speed so the engine will still run), run Seafoam through the system, reconnect the MAF, reset the ECU, and go on your merry way.

 

Regardless of the fuel system, I typically do the following for a Seafoam intake treatment:

1. Disconnect MAF, if equipped.

2. Remove air intake tube from throttle body: this is the easiest and most direct way to introduce the Seafoam, plus it does a good job of cleaning the throttle and is guaranteed to hit all of the cylinders.

3. Notice any build-up on the throttle plate. If it's excessive, you may want to use throttle body cleaner to get the bulk of it, then let it evaporate.

4. Start the engine.

If you've disconnected the MAF, the engine will run a little rough, but it should run and respond fairly well to the throttle.

5. While working the throttle linkage from the engine compartment (or with a helper working the accelerator, I guess), SLOWLY pour/spray the Seafoam directly into the throttle. You'll use about 1/3 cup or however much it says on the bottle/can/whatever. Pouring/spraying continually, you'll be giving the engine just enough gas to keep it from stalling up until the end: when you're just about out of Seafoam, close the throttle and dump in the remainder; the engine will stall. Leave it off for a minimum of five minutes; I don't think there's an upper limit, so I usually give it 30 minutes or so to more fully dissolve the heavier crud that may be in the system.

6. Reassemble the intake during the waiting period. Also reconnect the MAF if disconnected.

7. After the waiting period, start the engine. It should fire up almost immediately. It will smoke like nobody's business for between five and ten minutes. You can use this time to visually inspect the exhaust for leaks or anything.

8. It's generally recommended to change the oil and/or spark plugs after a Seafoaming, but not mandatory. I usually Seafoam the oil and fuel about a week before running it in the intake, then take care of the maintenance (change oil, clean/replace plugs, replace fuel filter if needed) all at once.

9. If the CEL remains illuminated with an MAF error, reset the ECU; otherwise, you're done.

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