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DIY deep fuel injector cleaner


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Does anybody have any recommendations on ways to deep clean Subaru fuel injectors? I'm not talking about that liquid you add " every 3 thousand miles" to your gas tank.

 

My 2000 GT has been pinging since before 30,000 miles - currently have 52,000. Have used mid-grade gas for a year to to try to counteract. Have replaced anti-knock sensor -- no difference. Subaru dealer says I need a fuel injection cleaning for 129.00. Is there a DIY throttle body alternative?

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There are tune up places that will do that injector cleaning, but I'm not sure it is worth the money.

 

You could always pull the injectors and clean them with carb and choke cleaner by setting the tips in a bath of the cleaner.

 

I tend to believe that with the additives in most gas today, the injectors should stay pretty clean, but that's just my OPINION.

 

As far as the throttle body, that is just for airflow in most newer cars. Putting anything there won't clean the injectors. Maybe your temp sensor is causing the timing to advance or retard when it shouldn't.

 

Does it ping when the engine is cold as well?

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Throttle body and fuel injectors are sifferent. But both can be done, and both help. Maybe put a can of Seafoam in the gas tank. It is hard to find, but it works. Most typical FI cleaners burn harder than gas, this one is opposite it is more oil based and cleans very well, at least it works well with my 215,000 mile Impreza!

 

Cleaning the TB is easy, take off intake to throttle body, get TB cleaner and spray it in and use paper towels (some people hate to use paper towels) to wipe around the inside of the TB. if you want to, and it helps. Plug a screwdriver on the outside of the TB, by the cables to hold the valve open. spray in there and wipe it in there to. If you do this try to focus on spraying the sides of the TB and not down the intake manifold.

 

Hope this helps. If you need more in-depth info PM me!

 

Max

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me myself and I

suggest if you cna do it

to find a old fuel injection pump

dig up a fuel injector driver schematic

run the fi pump to a small tank your preferance of injector cleaner

and position the injector so it dumps back into the tank

and run this little setup for about half hour to hour on each injector

btw i do suggest some kind of fuel psi regulator as well

 

it *should* do a decent job of cleaning injectors <or tbi stuff just take off the tbi and put it over the cleaner container

 

just something i been thinking of doing .. for a while

but never have gotten to the reality part of the idea yet :)

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try the seafoam. that stuff works great. stay away from the other dump in FI cleaners. they work okay on the injectors as long as you run your engine hot every time you run it for that whole tank of gas. but if you go a short distance and it doesnt get hot enough that stuff wont burn and it can gunk up the injectors and will foul your plugs.

 

I used the STP kind in my jeep wrangler, whose engine runs very cool. and it made a real mess. seafoam fixed that and made it run better then before.

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Tiny, Yes it does ping when the engine is cold and when it is hot - doesn't seem to matter.

 

I think I will try a combination of all of the suggestions. btw, where can you get this Seafoam? Sounds great.

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FWIW. A few add-to-fuel ones work well. Techron, Redline S1-1 (approved by BMW), BG44 (very aggressive), and of course Subaru have the spray stuff that cleans TB etc. Even the non Sube dyno tune place that does mechanical work for me carries the OEM Sube stuff and swears by it.

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Yeah, my fuel injectors went bad at 211,000 miles on my 93 Impreza.

 

I am not sure where you can get seafoam in oregon. It is about a 16 oz white steel can, it is shaped like Marvel's Mystery Oil. Maybe if you do a google search it can tell you where you can find it locally.

 

Maybe carquest, or napa. I know here in illinois Auto Zone don't have it.

 

Max

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seafoam works well

and the injector driver things i know of usually use pulse width modulation to control the injector opening and closing

 

still rebuilding my collection of fuel injection stuff after losing 60 gigs of data ackk!!!! and then had a power failure whiel trying to recover it double ack!!!!

so just starting over

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I don't think my fuel injectors need replacing. When I had my 30,000 mile service done at the local Subaru dealer, they said they were dirty and needed to be cleaned . The car was pinging at that time occasionally, that's why I was thinking the problem could be the fuel injectors. Several months later it was pinging more often, so I brought it in for service. They said the pinging was "within normal range" ( like any pinging should have a normal range ) and attributed it to my Ganzflow intake, so they refused to fix it. Ok, maybe I should have removed the intake first but it pings with or without it. I have used Techron -- no difference. Reset the ECU 3 times. It seemed to help right after I did it, but then went back to its normal pinging. Excuse me for my ignorance, but what is a pulse generator? btw - this dealer just replaced my radiator free under warranty this week when my boyfriend discovered a small seam leak near the bottom rad hose. And I wondered where that slow loss of coolant was coming from. Thought it might be a head gasket. I wonder if others had this problem.

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I think your pinging could possibly be caused by carbon deposits in your combustion chambers. The carbon acts as a sponge, soaking up some of the fuel and leaning it out, making it ping. I motorvac'ed my Legacy at like 185k and I swear it added another 15HP.. It only cost me about $20 to do it, but if your car is still under warranty, take that intake off and take it in and have them look at it.

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A pulse generator is used to create a series of electronic pulses that would simulate what your ECU puts out to the injectors. You'd need to know voltage requirements for the injector before you even thought about setting up something to clean them.

 

As you said, you don't think they are bad, and I don't either. I am surprised you don't have any fault codes in your ECU with that problem.

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ummm hondasucks..

it was my understanding that the carbon deposits would get hot enough to glow at times creating hotspots that would preignite the fuel-air mix

i'll have to go back through my mountain of books again to make sure i am remembering correctly <really bad memory> :)

 

this works for carbon removal

most of the time

go get a vacum T from a parts store and a small aquarium air regulator

find a source of manifold vacum put the t in and the aquarium thingy

and run a hose into a bottle of marvel mystery oil

adjust the regulator so you notice smoke out the exhaust and go for a drive with mid range rpms

it might freak out teh ecu if your running fuel injection and its gonna smoke alot

but it should clear out alot of the carbon crud

also regular highway driving helps alot also

i doubt mine has much carbon in it sicne i am on highway 30 everynight from longview to st'helens oregon

and tend to get on it more than i should

at least i know its cleared out :)

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ummm hondasucks..

it was my understanding that the carbon deposits would get hot enough to glow at times creating hotspots that would preignite the fuel-air mix

i'll have to go back through my mountain of books again to make sure i am remembering correctly <really bad memory> :)

 

this works for carbon removal

most of the time

go get a vacum T from a parts store and a small aquarium air regulator

find a source of manifold vacum put the t in and the aquarium thingy

and run a hose into a bottle of marvel mystery oil

adjust the regulator so you notice smoke out the exhaust and go for a drive with mid range rpms

it might freak out teh ecu if your running fuel injection and its gonna smoke alot

but it should clear out alot of the carbon crud

also regular highway driving helps alot also

i doubt mine has much carbon in it sicne i am on highway 30 everynight from longview to st'helens oregon

and tend to get on it more than i should

at least i know its cleared out :)

 

I wonder if you're significantly shortening the life of your cat. by running that much MMO through it. Just thinking out loud...

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well i suppose you would if you ran it continuously

just the same way a car that burns oil will mess it up

 

and thats kinda what i meant by the hot carbon spots

since its the edges that are thin and get the hotest

thats why any motor i tear downf or a rebuild i spend some time with a die grinder smothing out all sharp edges in the heads

<that also helps when done to the oil return passages helps it get back to the pan faster

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About the catalytic converter, will any of the deposit residue from cleaning the combustion chambers plug or harm it?

 

Has anyone tried adding just a little bit of diesel fuel when the tank was about a 1/4 full and running it down the freeway, then filling it with premium?

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the carbon deposits "could" plug up the cat.. but if you have that much carbon .. well thats gonna be teh least of your worries :)

 

usually the carbon will break up once it breaks loose

especially if you have a turbo

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