gas and gas mileage

[viclava]

I have 92 legacy LS, Ever since I bought it a year ago. Anytime I try to put unleaded gas it pings and knocks. Like the tanks I use to drive... I have been putting Premium and it's just fine. it idles great and runs just fine, but I didn't think it suppose to need premium, unless running a turbo unit.

Any ideas out there?
Vic

[skid542]

When was the last time you did a general engine tune-up? You know, plugs, wires, filters, fuel injector cleaner, etc. I would recommend Sea Foaming it too (do a search and all will be revealed). Sounds like your engine may just be generally dirty inside and needs the higher octane to compensate. BTW, all gasoline these days are unleaded .

[viclava]

What is Sea Foaming????

[gnuman]

SeaFoam is a brand of "top engine cleaner" that many Subaru owners swear by, as it works very well to remove the built up "gunk" that sometimes collects in the combustion area of our engines. Cheap gas will create more of this gunk as it does not burn as cleanly, leaving deposits. the can comes with a plastic tube that you connect to a vacume line next to the Throttle body, and stick the other end into the can. The vacume will suck the cleaner into the engine where it cleans out the deposits (creating a lot of smoke, and a fair bit of stink) until it is all burned off. if you rev the engine while sticking the tube in the can, about the correct ammount will be sucked into the engine before the engine chokes and dies (then you replace the vacume line, and start the car to finish cleaning it). Put the remainder into the fuel tank to clean the injectors. I have not done this myself, but I have heard a great many very good things about this product, and will be doing this as soon as my local supplier gets some more in stock (a lot of shops will watch the store and buy out the whole stock the day it comes in. The stuff is *that* good.)

[Legacy777]

www.seafoamsales.com

[bluesubaru]

I like it, just used it last week. Fed some into my vacuum line and the rest into the gas. My vacuum gauge reads almost 21inMH, instead of 19.5. Gas mileage is about the same, right at 19-21mpg. Oh yeah.

[viclava]

Oh boy, I tried the Sea Foam. It looked like the James Bond Smoke screen after I sprayed that stuff in. I haven't tried pumpoing regualr unleaded in yet. but am going to soon to see if it helped. A couple of my neighbors thought my car was on fire.
Scott

[bluesubaru]

wow that is a lot of smoke.