87 XL GL10 Turbo / Owners Manual recommends Real Gasonline

[Chuck_S]

Hey Subie Peeps,

 

Just got an 87 Wedge, and love it!

 

I was reading the Owners Manual which recommends real gasoline, and not the 10% Ethanol they sell everywhere.

 

I recently filled up with Shell 93 Octane V Power thinking this was probably the closest thing, however the car started sputtering, and bogging down.

 

I asked a guy at Autozone, and he recommended a Lucas additive.

 

I definitely don't want to ruin the engine, or deteriorate any of the gaskets/rubber etc.

 

What to you recommend for a 30 year old XT like this as far as gasoline and/or additives ?

 

Thanks,

Chuck.

 

Edited June 25, 2017 by Chuck_S

[idosubaru]

You can run any gasoline you want. 93 octane is pointless and a waste. If you bump the timing up a bit you can make a few extra imperceptible hp (unless you dunk it) on higher octane.

 

If there is rust in the gas tank or old gas from the past - that damage is already done and needs addressed.

 

It's only a problem if you let it sit for extended periods of time, like years. Drive it every day and you can run it to 300,000 miles all day long on any gas.

[idosubaru]

Sharp XT, very nice!

[GeneralDisorder]

As mentioned you aren't going to hurt it. Don't use any additives.

 

Your issue is not fuel related. It's sh*tty old EA82T fuel injection related. Do a tune up, pull the injectors and clean them, and hope the head gaskets last a while. When (not if) they blow and the heads crack right half in two - swap in a real engine from a donor Legacy.

 

Parts availibilty for that engine is basically non existent. You can't buy oil pumps for them anymore - or most of the internals. Forget about fuel injection parts. Used is thr only option. Basically they are a dead platform and suitable only for collectible status starting real soon here. If you actually want to drive it then a more modern power plant will eventually be needed.

 

GD

Edited June 26, 2017 by GeneralDisorder

[Chuck_S]

@grossgary Hey thanks for the info, yah well I won't be needing that $42 dollar fill up again then, haha. Good thing is the only rust I've found so far was in the sunroof lip, got it from Oregon, and was very clean, and only 89k miles. Paint is ok, except for the rear bumper, peeling everywhere, gonna get a few quotes for a paint job on that.

 

[Chuck_S]

 

@GeneralDisorder Ahhh, ok, I'll get it tuned up and have 'em clean the fuel injectors, makes sense. The good news is that it's only got 89k miles, so hopefully I'll get a lot more miles on this before the head crack.  Thanks for the info on the Legacy powerplant, what would be something I should be looking for as a donor? (year/model etc)  I hope to keep this XT for a long time, but would be nice to have the spare powerplant as a backup when things go bad.  Any reputable shop should be able to clean the injectors? Or should I bring this to a dealer?

 

[GeneralDisorder]

The dealer wouldn't know what to do with an XT. Half the time they don't know what to do with modern Subarus.

 

Pull the injectors and have them cleaned and flow tested. There should be an injector shop somewhere near you. Or you can send then out to places like witchunter, Southbay, etc. It's just a good idea to know where you are at with any injector that old.

 

GD

[Chuck_S]

@GeneralDisorder Hey thanks GD, I'll definitely do that, checking for injector shops in the chicagoland area now.  Really appreciate your insight on this 

[naru]

 

You can run any gasoline you want. 93 octane is pointless and a waste. If you bump the timing up a bit you can make a few extra imperceptible hp (unless you dunk it) on higher octane.

 

If there is rust in the gas tank or old gas from the past - that damage is already done and needs addressed.

 

It's only a problem if you let it sit for extended periods of time, like years. Drive it every day and you can run it to 300,000 miles all day long on any gas.

This is BS.

You want the highest octane possible on a turbo car.

Even 93 is still crap.

[golucky66]

Personally, on my 04 Baja Turbo (much newer, i know) but if i run anything less then 91 octane, my car retards the timing so much that it feels like I'm driving a NA car.

Most places in my area only have 93. So that's what i use. Though the few times I've found and ran 91 i never noticed a different from 91-93.

[Numbchux]

 This is BS.

You want the highest octane possible on a turbo car.

Even 93 is still crap.

 

No

 

 

If the ignition timing is not tuned for high octane, it will not be better. Putting 110 in a car tuned for 87, turbo or not, is not better.

 

 

That said, if you're tuning for it, yes, higher octane is generally better for a turbo car. But a stock EA82t is not a high performance engine running on the edge of what's possible....far from it.

 

 

 

 

I don't think the Ethanol they add to the fuel now is comparable to what was available when that owner's manual was written. I wouldn't (and haven't, although I've never personally owned a turbo car) worry about 10%

[Numbchux]

Personally, on my 04 Baja Turbo (much newer, i know) but if i run anything less then 91 octane, my car retards the timing so much that it feels like I'm driving a NA car.

 

This is not relevant, as the EJ255 is tuned for premium fuel only. So yes, never run anything less than that if it can possibly be avoided.

[golucky66]

 

This is not relevant, as the EJ255 is tuned for premium fuel only. So yes, never run anything less than that if it can possibly be avoided.

See i assumed we are talking about the EA82T which i wasn't sure if it required 91+. If it did require 91+ running lower octane then what is recommend can cause timing to retard to prevent knock. At least on all modern cars.

 

So does the EA82T only require 87?

Edited June 26, 2017 by golucky66

[GeneralDisorder]

This many years later - who knows. The thing probably has detonation from any number of electrical gremlins, carbon build up, poor flowing injectors, etc. Unless you can monitor the knock sensor I would err on the side of caution and run the highest you can get. These engines don't have particularly robust rod bearings and it *is* a turbocharged application making it much more violent should it get into serious detonation territory. For the sake of 30 year old unknown fuel/ignition system on a turbo car - run the highest octane you can get till you know for certain it is ok with something less. 

 

GD

[Subaru Scott]

I had dropped an EA82T in a hatch that I drove for many years on regular gas. Even had a brake spring on the wastegate that bumped it up to 12 psi 

 

Having timing set appropriately is critical. And, as GD stated, the injectors must be performing well.

 

I did run premium from time to time during "recreation," and advanced the timing a few degrees to take advantage.

But during my weekly long highway commute, I would back it off just slightly for maximum mileage on regular gas. City driving required a little less advance even than that.

 

I did burn a piston once, racing my buddy up a long freeway hill, with my family in the car and the "commute" timing setting, but that was just stupid. 

Yes, they do have a knock sensor, but the ECM will only adjust so much, and not very quickly. 

 

So, all that being said, in your case I would run premium, just to be on the safe side. Unless you plan to use it as a commuter, and keep tabs on your timing. But not for a hobby car.

[idosubaru]

This is BS.

You want the highest octane possible on a turbo car.

Even 93 is still crap.

Subaru engineers designed it to run on low grade gas. Generic one size fits all ideas don't veto Subaru engineers for everyone. Generally I agree, its a decent one size fits all approach for turbo engines but specifically, this is a neanderthal EA platform not an EJ.

 

In proper running condition EA82Ts run all day long on regular gas, as Subaru intended and designed them.

 

So as a diagnostic, "fix", causative agent, or starting point on a car with issues, it's highly unlikely to be what he needs to be thinking about. theres some merit to running high octane but he shouldn't get any warm fuzzies or hope from it either.

 

GD makes a good point that starting high while troubleshooting is reasonable risk mitigation.

 

Fix the real issue then ask about fuel choice.

[Chuck_S]

Thanks for all of the great info, yep I'm going to take it in to an import shop in Schaumburg IL, to got diagnosed this weekend.

It may have just been coincidence, but Tuesday I was almost on empty, and filled up with that Shell 93 v Power, and that's when it started losing power every 10 mins or so.

Had to put it in neutral, turn it off/on and then it would run good for another 10 minutes or so.

Anyhow this mechanic said he used to work at a Subaru dealer in the mid 80's and has worked on many XT's, and also has the right equip to clean the injectors and to the flow test, but he was guessing it may be something overheating with the fuel pump.

As soon as I find out what's happening, I'll post it here.

Thanks again for all the great info, really appreciate it, great community!

 

Chuck.

[Subaru Scott]

What you're describing sounds like a clogged fuel filter and/or clogged screen in the fuel tank. When you filled up, it probably stirred up sediment on the bottom of the tank. 

Was the car sitting for a long time before you bought it? When you shut it off, the pressure of the fuel after the filter will backflush it just enough to let fuel flow again for a short time.

[Chuck_S]

@Subaru Scott  That sounds very logical, yep it was sitting for a month or so in Portland, and I trailered it back to Chicago.
Yah it's so crazy that the on/off of the ignition will clear it, and it will run good again for a while.  
There was a ton of dust in the area I bought it, he lived on this super long dusty road, so sediment/dust etc actually sounds like it may be the problem

Many Thanks!   Hopefully I'll get to the cause of it this weekend sometime, and will post.

[Subaru Scott]

Yeah, the first time I had that same thing happen, it really baffled me. Quite different than the symptoms of a clogged filter on a carbureted engine. I ended up just turning it around backwards, and backflushing it into a bucket. All the goo came out, and it ran fine afterwards!

[idosubaru]

If it does it again and won't start you can test fuel supply in a matter of minutes.

 

pull the fuel hose line in the engine bay (only need screw drivers). Then crank the car - if fuel pours out like a hose it's good. If not, it's bad.

 

You only need to unscrew one Phillips head screw on the hose clamp. The hose will be so tight to remove you'll have to pry under the end with a flat blade screw driver, twist first with channel locks or cut it back about an inch with a knife. Otherwise it's super easy.

 

So far that's diagnosed every Subaru fuel supply issue I've seen and is super quick.

 

I would also disconnect the O2 sensor. The ECU doesn't typically use that at first start up, maybe car runs fine without the O2 and then when the ECU starts using O2 data it's a dirty signal.

 

This is also super easy and quick. Not likely your issue but it's so easy and free, and I've seen it happen once on an XT, it's worth a shot.

 

Oddly that car wasn't giving check engine light or codes for it either.

Edited June 27, 2017 by idosubaru

[GeneralDisorder]

If it does it again and won't start you can test fuel supply in a matter of minutes.

 

pull the fuel hose line in the engine bay (only need screw drivers). Then crank the car - if fuel pours out like a hose it's good. If not, it's bad.

 

You only need to unscrew one Phillips head screw on the hose clamp. The hose will be so tight to remove you'll have to pry under the end with a flat blade screw driver, twist first with channel locks or cut it back about an inch with a knife. Otherwise it's super easy.

 

So far that's diagnosed every Subaru fuel supply issue I've seen and is super quick.

 

I've had at least three occasions where fuel pressure was low but still present. It can happen. I've had improperly installed pumps partially blow the hose off their nipple, there's the infamous cracked pressure cap issue on the early 2000's fuel pump assembly, and I've seen the turbine wheel strip it's D shaped drive inside the pump and spin but not produce any pressure. Seen various other slow and intermittent pump due to brush issues. *usually* *Subaru* pumps either work or they do not. But it's not a 100% guarantee that if fuel pours out an open line the pump is good. 

 

It's best to actually check the fuel rail pressure. And if possible to watch the current draw of the pump, calculate it's RPM, and compare to a known good scope reading.... if you have the information and ability to do so. 

 

GD

[Gloyale]

There is a cone shaped screen in the inlet of the pumps that can get clogged too.  

 

PITA rump roast to pry out but worth checking.

[crazyhorse001]

My 2cents worth on premium vs others. If you have a local farmers co-op they carry pure gas. Some other stations carry it as well. The rubber parts of an older car's fuel system were NOT designed for ethanol, and will degrade with its use. My classic subie gets co-op gas exclusively. My timing is advanced to take advantage of premium, but at the factory settings it should be just fine on 87 octane. As long as its pure gas. I dont reccomend fuel additives, as most are alcohol based (read ethanol) and can do more harm than good on older fuel systems.

My free advice, your mileage may vary, and your opinion may differ

[idosubaru]

Right, didn't mean to imply that intermittent or partial failures don't happen. It can confirm fuel issues but doesn't rule them out is what I meant, I kind of assume people don't think things are black and white but I shouldn't do that.