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Low town mileage & How to inspect fuel injectors on '92 Legacy


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I want to inspect my fuel injectors because of low town mileage.

 

Anyone have the scoop on how to do this - after accessing the injector, how to PULL it out?!! : )

 

Main issue: I am getting LOW in-town mileage on this '92 Legacy L, with 186,xxx miles. (runs great and passed smog with new car values)

 

I get 27-28 mpg on the road, but only about 15-17 in town.

 

Really need your suggestions or insights!

 

I am installing an onboard hydrogen injection system and need to get my base performance straightened out.

 

Thanks for your help!

 

"Dusty"

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Is it an auto or manual? Do you drive like a grandma in the city? It still seems sort of low even for city driving, but if you are really stomping on the gas and brakes alot, maybe not.

 

What kind of hydrogen injection system. I'm convinced that those violate the first law of thermodynamics, but I'm also thinking of trying one if they're not too expensive, mostly just to see if the supposed combustion efficiency increase really does outweigh the losses from turning electricity from the alternator into hydrogen.

 

EDIT: this should actually be in the New Gen forum. Legacies aren't old gen.

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Have you checked your O2 sensor, that's usually the first reason for a drop in gas milage and may not always trip a code.

Also there is still alot of crap gasoline out there. I would do a few tanks with Amaco or BP since they seem to have the best gas right now to get a true mileage.

Now out of curisoty, and since i worked in the H2 industry, just why and what are you installing on your car. A word of caution, H2 has a lower power density the gasoline, and in a power to power comparison, you need more h2 to get the same power as a gallon of gasoline.

Before you do anything to your fuel delivery system you need to tune the car up to get a good baseline. Also check for any codes. You do not say if this is a manual or an automatic. I am going to assume this is 2.2L .

 

nipper

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Nipper, thanks for your reply!

 

I have already installed a new dealer O2. Have run injector cleaner, and done the acetone thing (~3 oz. per 10 gal. You can search on this...interesting). Does fine on the hiway. Why not in town (I drive like grandma)

 

Any idea how I can pull the injectors to inspect?

 

You can check out http://www.aquatune.com in answer to your H2 enquiry as to why and what. (I am master distributor for N. California and want to get this old Subaru up to good base values for aquatune test on it.)

 

This is a Legacy L w/automatic & 2.2. New O2, new air filter, new plugs, new wires.

 

Thanks again,

 

Ron "Dusty" Rhodes

 

----

 

 

Have you checked your O2 sensor, that's usually the first reason for a drop in gas milage and may not always trip a code.

Also there is still alot of crap gasoline out there. I would do a few tanks with Amaco or BP since they seem to have the best gas right now to get a true mileage.

Now out of curisoty, and since i worked in the H2 industry, just why and what are you installing on your car. A word of caution, H2 has a lower power density the gasoline, and in a power to power comparison, you need more h2 to get the same power as a gallon of gasoline.

Before you do anything to your fuel delivery system you need to tune the car up to get a good baseline. Also check for any codes. You do not say if this is a manual or an automatic. I am going to assume this is 2.2L .

 

nipper

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Hi Zyewdall,

 

I did figure out that this post should have been newgen!

 

It is an auto.

 

I would still like to know how to pull and inspect injectors! : )

 

I am wanting to get normal base values for this Legacy before testing injection. See http://www.aquatune.com for what I am up to. I am Master Distributor for Northern California.

 

I drive like g'ma. I like the best mileage, not thrust (though the AQT will deliver thrust).

 

Regards,

 

Ron "Dusty" Rhodes

---

 

Is it an auto or manual? Do you drive like a grandma in the city? It still seems sort of low even for city driving, but if you are really stomping on the gas and brakes alot, maybe not.

 

What kind of hydrogen injection system. I'm convinced that those violate the first law of thermodynamics, but I'm also thinking of trying one if they're not too expensive, mostly just to see if the supposed combustion efficiency increase really does outweigh the losses from turning electricity from the alternator into hydrogen.

 

EDIT: this should actually be in the New Gen forum. Legacies aren't old gen.

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The injectors are a pain to remove. The best way to remove them is to squirt some penetrating oil around the seals, and twist them. The twisting works about the best to remove them.

 

That's a pretty substantial difference in mileage between city & highway. Are you doing a lot of short trips for city driving?

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Josh,

 

Thanks. I will try the penetrating oil. Are the injectors held by vacuum or anything, or just the seals...

 

Just normal back and forth across town, 1, 2, 3, or so miles per trip, with stop signs and lights.

 

-Dusty

 

The injectors are a pain to remove. The best way to remove them is to squirt some penetrating oil around the seals, and twist them. The twisting works about the best to remove them.

 

That's a pretty substantial difference in mileage between city & highway. Are you doing a lot of short trips for city driving?

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Josh,

 

Thanks. I will try the penetrating oil. Are the injectors held by vacuum or anything, or just the seals...

 

Just normal back and forth across town, 1, 2, 3, or so miles per trip, with stop signs and lights.

 

-Dusty

 

If it's not getting up to operating temp, it could explain the poor gas mileage. My GL takes about 3 miles through the city to get up to full temp usually. I try to bike if I'm going less than 5 miles or so (and don't need the cargo space).

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be sure to remove the cover inside the cargo area under the carpet and unhook the fuel pump connector before you start,run car until it dies,still will be a little pressure.i had to slip a pocket knife blade under them to get them out,i presoaked with kroil.

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Youse guys are great! :)

 

Confirm advice to unhook fuel pump connector, use penetrating oil & may need a knife to lift injectors. And, yes, operating temperature would be an issue; but owners and shops have told me I should still be getting higher city mpg, so I am searching it out. -Dusty

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OH ok its water injection, NOT hydrogen injection. Now that makes sense. In all honesty unless you have a very expensive fuel injector test setup, pulling out the injectors is not going to tell you anything. Also if you decide that they are dirty and try to clean them agresivly you will ruin them.

The best bet is to (i cant beleive im saying this) get a fule injector cleaning service from a garage. I dont normally believe in them unless you have a drivability issue and have ruled everything else out. ONt totally by the entire water injection thing, because it it was true, every car out of detroit would have one. They work best with high compression engines, turbos, to drop combustion temnperitures and reduce pre-ignition. I would have a compression test done on your engine first. If you have weak piston rings you may be inducing water in the oil and thats not a good thing. ALos when you first use it it is going to scare the hell out of you.

In the good ol days one would use a spry bottle of water to decarbonize an engine. You would spray the water donw the intake, NOT let the car stall, and make sure its pointed away from your neighbors, as it would proiduce alot of smoke.

I am not seeing any dyno tests or science to back up thier claim. The dyno tests are done at idle, not at peak on the 1.8L engine, thats a bogus test. It worked on the harley cause its an air cooled engine, and thats where i would expect some what of a gain.

400.00!!!!!!!!!!!!!!!!!!!!

do you realize how much gas you have to save you have to burn to recoup that cost.

They give emission reports for various cars, and yes that is where it would work also, but if you look closely, the cars they site are ancient, They call it DEQ Studies, and there is no such thing. They dont even site SAE test practices for anything. ONly a 30 day warrenty ...

 

Man i smell a scam

 

i have a nice bridge in brooklyn to sell if you are interested,

 

nipper

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If you're only driving a mile or two, you're going to get considerable less mileage then what the "standard" city mpg is. I drive about 1-2 miles to work every day in my nissan truck, and the mileage is absolutely horrible, yet if I drive on the highway, I get great mileage.

 

I really doubt anything is wrong with your car. At most, I'd recommend you change your thermostat....and/or possibly the coolant temp sensor. I just really can't see anything being wrong with your injectors.

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Josh,

 

Much appreciate your comments. Will do as you suggest.

 

If you're only driving a mile or two, you're going to get considerable less mileage then what the "standard" city mpg is. I drive about 1-2 miles to work every day in my nissan truck, and the mileage is absolutely horrible, yet if I drive on the highway, I get great mileage.

 

I really doubt anything is wrong with your car. At most, I'd recommend you change your thermostat....and/or possibly the coolant temp sensor. I just really can't see anything being wrong with your injectors.

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The water injection system definitely reeks of scam, especially the crap about it converting water into hydrogen by frequency resonance blag blah blah. Sorry, doesn't happen. It takes a little more than a hot engine to split a water molecule and release a significant quantity of hydrogen. Frankly I wouldn't waste your money on it, but hey, maybe there is something to it depsite the bogus explanation.

 

 

 

Josh,

 

Much appreciate your comments. Will do as you suggest.

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back in the 70s i dont remember who offered the kit but you got a jug[looked like a recovery tank] some hose and a adjustable valve,you ran the hose out of the jug to the valve to a vacum line on carb,some people raved at super gas milage,remember how good your car runs on a rainy day? dont know.

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