fuel economy question, speedometer/4EAT question

[notnowles]

I am curious as to what others find to be sort of average fuel mileage for a car similar to mine. It's a G1 (1990) sedan, EJ22, 4EAT with 115K miles behind it.

 

I don't have a working speedometer most of the time (stripped gears inside the case, so I am using my GPS as a speedometer...) and today did 300 miles on the highway. Seemed like I used quite a bit of gas (but maybe it's the $3/gallon figure that is affecting my perception!)

 

Anyway, I will do another 300 miles tomorrow, so at some point I can try to come up with a rough estimate of fuel mileage.

 

Another question is that, with the speedometer not working much of the time, I get a "Check Engine" light when the speedo is out, and I wonder if it is affecting the 4EAT. Trans shifts smoothly, but sometimes when I lift my foot off the gas at high speed and then depress again, it gives the sensation that it is either shifting out of and back into high gear, or perhaps the converter is unlocking/relocking???

 

I realize the 4EAT really wants a functional speedometer sensor, but I don't have the wherewithal right now to pull it apart and replace those gears. It looks to be a long, long way into them!

 

And... Merry Christmas to all who celebrate it!

 

And thank you for the help/suggestions/opinions. This board is absolutely invaluable to a guy like I who has an ancient Subaru!

[nipper]

Yes yes and yes.

 

There is a Vehical speed sensor in the spedo head. I bet the CEL is throwing a code. I wonder if the other VSS sensor is operating. In this car since I think it is a cable operated spedo when one VSS fails the other does not power the spedo.

 

Are the gears stripped in the tranny or spedo?

 

This will affect your fuel economy, how much fuel on 300 mile fillup? What is the temp outside? What is the avg speed/cruising speed?

[notnowles]

Yes, this car has a cable operated speedo, and the VSS is in the speedo head. The gears in the tranny are stripped. They were stripped by a seizure of the little "takeoff" device which threads into the top of the tranny to which the cable attaches. I spent a lot of time trying to fix it and diagnose it when it happened. (Sigh...)

 

I replaced the little takeoff device and cable and checked the speedo head. The speedo head is good. At this point, the speedo operates enough at low speed, especially when taking off from a stop, to keep the Check Engine light from coming on.

 

It's certain that the lack of a functional VSS is causing the CEL to appear. The light will go off anytime the speedo kicks in, which it does from time to time.

 

I'm just wondering how/if this would affect fuel economy. I was pushing it down the road today, 75 and 80 much of the time, so I wasn't exactly driving for economy.

 

I will know after tomorrow's drive as to how much fuel, etc. I was just wondering what is "normal" for the car. EPA shows 19/26 and I am probably somewhere in that range.

 

I think I saw a post once here that described pulling the differential apart on the passenger side to allow one to get a hand back inside the case to access the smaller driven speedo gear.

 

Subaru has some great engineering, but I have never seen another car that has the smaller driven speedo gear attached from inside the case...

 

Oh well...

 

All in all, for a 20 year old automobile with 115K behind it, I think it's doing pretty well, all told.

[Buick350X]

A good general read

 

Fuel Economy, Engine Efficiency & Power

 

http://www.viragotech.com/fixit/FuelEconomyEngineEfficiencyPower.html

[nipper]

The VSS the car can not tell how fast it is going so it may be going into open loop mode and that is generally inneffecient. This mode uses pre-programmed parimieters instead closed loop which constantly adjusts the F/A ratio. It sounds like the other Vss sensor may have issues too. YOu will not have AWD at high speeds since the AWD can not tell the speed differential between front and rear of the car when the CEL is on.

[bheinen74]

I think we subaru owners have to chalk up speedo failure as REALLY common on Subarus.

So far, I had one go out on a 94 turbo wagon, had one go out on my 92SVX, my current legacy turbo has it acting up, and my brothers 99 outbak had to have the odo replaced due to speedo quit, and my dad's 98 forester was previously replaced too.

I see LOTS of threads on this issue, here, on legacycentral, on SVXnet, and outback.org.

 

I think we have to just assume at some point, the speedo may quit on us at any time. Pretty silly subaru cannot figure out a better setup.

[idosubaru]

my brothers 99 outbak had to have the odo replaced due to speedo quit, and my dad's 98 forester was previously replaced too.

as you know, the 99 odometer is known problem area. wouldn't surprise me if there's some 98 or 2000's bleed over years too. they do seem less reliable than the old school speedo set ups.

[notnowles]

I did another 300 miles today, most of which was highway, but not Interstate, so speeds were generally much lower than yesterday's 300 mile round trip, which allowed 75 and 80 just to keep up with traffic.

 

The CEL was actually on very little today. The gears inside the tranny "catch" just often enough to give me the periodic thrill of seeing the needle move, which turns off the CEL.

 

My guess is that the AWD and closed loop are intact if the CEL is off (?)

 

Another little aside to this saga is that, last winter, when the speedo was not working at all, due to the seizure of the little takeoff device and broken cable, the tranny "Power" light would flash a # of times upon start up, which I read somewhere (probably here) meant that the AWD system was disengaged and the trans was in limp mode.

 

Now, with the periodic but random operation of the speedometer, I never get the flashing of the Power light when I start the car.

 

I believe that what I described as going in and out of gear at high speed is the unlocking/relocking of the converter when I lift my foot off the accelerator and then hit it again. This seems to happen when I do the lift/hit of the pedal between maybe 50 and 60 mph.

 

Perhaps this is happening more because the VSS is not getting its input.

 

I don't know...

 

My frustration is that the speedo in this car is just fine, but that blankety blank gear inside the case is stripped.

 

The body on this car is really beat, but mechanically, the car seems quite strong. I am the second owner, the first owner having been a friend, so I know the 114K to be actual, except that I am now putting miles on it which don't show...

 

The body is so rough that it's hard for me to justify going inside that tranny to change the speedo gears. That said, the car runs great.

 

It looks like it is doing right around 25 mpg, based on distance traveled and fuel purchased.

 

It's my winter beater, but I am going to keep my eyes on CL for a better body for which my car could be a donor vehicle.

 

Thanks for the input, and the link to reading material!

 

And I am going to do a search here for the info on the speedo gear replacement, just to give me something to ponder. I remember someone quite knowledgeable had an article about 4EAT work/overhaul with great photos, which showed the speedo gear installation.

 

Hope everyone here had a great Christmas!

[nipper]

25 is not too bad in winter. Blu gets between 16 in winter and 25- 26 highway. Normally it is 19-21 and 27-30

[MilesFox]

my 94 legacy gt 4eat 95,000 miles averages about 20-21 mpg across 300 mi of driving @ 65 mph average(some 60 mph, some 70mph, off and on snow driving at night) My variable factors are 15 inch wheels, and a cracked muffler flange.

 

Mine does go in and out of torque converter lock depending on how i ride the gas pedal, and what you describe seems normal to me.

 

My wheels are about 3mph off on the speedo, so my 301 miles i calculated for fuel economy is probably about 310-320 miles, and this my '21' mpg average.

 

With the oversize wheels, i get the torque converter dance at about 60 mph, and the car seems more efficient towards 70 mph.

 

I would think i should get 22-24 mpg with the right size wheels and a non-broken muffler. My economy in town is about 16-18, where it should be about 20 without the wheels and muffler issue.

[nipper]

If you have a head wind it will knock it down as Outbacks/Leggy are not all that aerodynaic.

 

Last time for a tuneup?

[notnowles]

Hey, I am glad to hear the fuel economy figures, which lead me to believe my old car is not doing too badly in that department.

 

The CEL is kind of weird. It hasn't been coming on much the last couple of days, which I believe is due to the fact that the speedometer is likely to kick in at low speeds, and my driving has not been all that fast the last day or 2.

 

I can induce it by letting the car idle in neutral for a few minutes, which is the AIC, if the code is to be believed. I still need to get my used one cleaned up, get a new gasket from the dealer, install it, and see what happens.

 

At least I have been able to narrow my CEL to 2 different things: the VSS and the AIC.

 

I am very happy to hear that the "converter dance" (I like that term!) happens to others.

 

You know how these things are: You have a couple of known "issues" and then you're paranoid with every little thing that happens that seems the least bit different.

 

With 115K, I am wondering how long the drivetrain in this car will live. I changed the ATF a couple of times in succession, and it is staying a nice pink color, and the engine certainly sounds good. Again, I'm a little paranoid, because I went through a dark period with bad injectors and they flooded the crankcase with gasoline...

 

That said, with the most recent change and 10W40 oil, the oil has remained clean and unpolluted, and the engine purrs...

[nipper]

Hey, I am glad to hear the fuel economy figures, which lead me to believe my old car is not doing too badly in that department.

 

The CEL is kind of weird. It hasn't been coming on much the last couple of days, which I believe is due to the fact that the speedometer is likely to kick in at low speeds, and my driving has not been all that fast the last day or 2.

 

I can induce it by letting the car idle in neutral for a few minutes, which is the AIC, if the code is to be believed. I still need to get my used one cleaned up, get a new gasket from the dealer, install it, and see what happens.

 

At least I have been able to narrow my CEL to 2 different things: the VSS and the AIC.

 

I am very happy to hear that the "converter dance" (I like that term!) happens to others.

 

You know how these things are: You have a couple of known "issues" and then you're paranoid with every little thing that happens that seems the least bit different.

 

With 115K, I am wondering how long the drivetrain in this car will live. I changed the ATF a couple of times in succession, and it is staying a nice pink color, and the engine certainly sounds good. Again, I'm a little paranoid, because I went through a dark period with bad injectors and they flooded the crankcase with gasoline...

 

That said, with the most recent change and 10W40 oil, the oil has remained clean and unpolluted, and the engine purrs...

 

 

115 K

 

That is just a child! With care the drivetrain major parts the sky can be the limit as far as life of the drivetrain

[notnowles]

Just a child, eh?

 

That's funny!

 

I have heard that they last a long time, but I guess I figure it's 20 years old...

 

If it continues to run well, my idea is to look for a better body, maybe a wagon, that might need donor parts from my car.

 

Thing is...

 

This car is so old, that I don't see many around with good bodies of this vintage. I live in an area with lotsa salt on the roads in winter, and it takes its toll. I can be patient, though, and perhaps something will come along one of these days.

 

As I recall, the engine in this car (1990) will fit a few years later (?), and the tranny (4EAT) maybe a couple of years later (?)

 

Of course, were I going to put this 4EAT in another body, I would certainly dismantle it enough to replace that speedo gear.

 

Meanwhile, the body doesn't look so bad sitting outside under a fresh blanket of snow!

[idosubaru]

if you really want one of these and would like to have one a very long time, seriously consider getting one from further away that doesn't have rust issues. not only will it last as long as you want it, the maintenance it needs won't turn into a debacle...like rusted bolts, sheared bolts, seized bolts, crusted bushings, etc.

 

thing is - it is more work in some ways - but the greater the search area you're looking it's not hard to find one for a really great deal.

[heartless]

seriously - 115K IS nothing for these cars - even for a 20 yr old one.

 

I have a 1990 Legacy LS wagon AWD 4EAT with just over 205K - runs and drives fine. not the prettiest car on the road, but not the ugliest either.

 

the other half has a 1990 Legacy L sedan, 5 spd, FWD with 250K and still going strong. again, not a real pretty car, but quite reliable.

 

so with decent care & maintenance, these cars will run for darn near ever - the bodies give out before the motor does - at least in the salt belt anyway.

 

oh yeah, for the record - winter time i get about 26mpg average mixed driving, summer is closer to 30 mpg

Edited December 27, 2010 by heartless

[nipper]

Say, how old is your thermostat? The gauge may look Ok but the car can be running cool.

[notnowles]

I appreciate the positives, and looking outside the rust belt for another example is a good idea.

 

Funny you should mention the t'stat...

 

I don't think the heater in this car is wonderful. I need to check to see how warm the engine is running. The gauge looks normal (a little bit below half).

 

I checked a local auto parts store for a t'stat, and they have in stock a 170 which they say is the standard temp for that car. I used to use that temp stat in other cars as a "summer" t'stat, but most cars I have dealt with since about the 80s had a t'stat setting of around 190.

 

If anyone else has experience with this question, I would be interested in your input.

 

I should follow up by saying that this car looks pretty bad, but it drives very well, feels solid, has a comfortable ride, and cruises nicely on the road, especially given its 20 year old status.

 

I need to track down a front exhaust pipe, that goes between the engine down pipe and the converter. Someone told me it's the same pipe that was used on a newer Forester, which is kind of hard to believe. Parts store says it's the same on all 90 -94 Legos.

 

Thanks again for the helpful suggestions and words of encouragement!

[nipper]

OE thermostat ONLY. Cheap aftermarket ones are too small for flow and dont have the jiggle valve which lets air through or any foam/bubbles from turbulance.

[bheinen74]

On any subaru never use a "local auto parts store for a t'stat"

only go OEM. some thread on here shows the pics comparing the whimpy flimsy aftermakert one to the genuine oem subaru part.

its like apples to bananas.