Hi guys. Lately after my Speedometer gauge went bad, my Check Engine light came on and when I start the car, the Power light flashes fifteen times and my MPG went down the hill, probably down to around 10-15 MPG (if not less), which is ridiculous crazy. I used to get 25-30 MPG so this is killing me.

 

First, I want to know if the Speedometer gauge going bad causes all of these to behave the way they do or am I facing a bigger problem here? If it's a bigger problem, I might just trash it as I don't want to spend too much money to keep it up.

 

Okay, this is on 91 Leggy 2.2 AWD Auto.

 

Thanks for any advice...

YOu lost a vss sensor, The car is in limp mode and will stay there untill the sensor id fixed. Poor performance is to be expected.

 

nipper

YOu lost a vss sensor, The car is in limp mode and will stay there untill the sensor id fixed. Poor performance is to be expected.

 

nipper

 

By VSS, you mean "Vehicle Speed Sensor," correct? So, the Speedometer gauge failure initiated this sequence, correct? Okay, that is better news. Thanks...

The VSS is inside the speedo, so replacement of the cluster with a used one is your best bet.

 

GD

The VSS is inside the speedo, so replacement of the cluster with a used one is your best bet.

 

GD

 

Thanks for the advice. Going to the junk yard right now. Hope that's the culprit.

 

JC

1991, the speedometer adapter is broken. In the early 90's, the speedometer was cable driven and the VSS was in the speedometer head. The adapter is on the passenger side, right where the cable enters the tranny. The cable is held on by a spring clip. Remove the cable, then unscrew the adapter from the transmission. Replace the adapter and put it all back together.

 

This was common and Subaru dealers stock this part.

1991, the speedometer adapter is broken. In the early 90's, the speedometer was cable driven and the VSS was in the speedometer head. The adapter is on the passenger side, right where the cable enters the tranny. The cable is held on by a spring clip. Remove the cable, then unscrew the adapter from the transmission. Replace the adapter and put it all back together.

 

This was common and Subaru dealers stock this part.

 

what he said, its not the head, its the cable.

 

nipper

Exactly when I was screwing around with my speedo cable and unplugged it I got a power light. Didn't drive crappy though and I didn't get a check engine light. If its not working at all there is a piece that often fails on the differential where the speedo cable plugs in that breaks.

 

http://bbs.legacycentral.org/viewtopic.php?t=32903&highlight=speedo

 

http://www.main.experiencetherave.com:8080/subaru/images/speedocablebase.jpg

Well, I replaced the Speedometer gauge with a used one (assume good) and it's still doing the same thing, remains zero MPH when driving. The Check Engine light went out a few minutes after driving, though, and it remains off. I'm going for the gear driver next (or adapter - whatever it is called). Had it ordered and should be here within a week if not sooner.

The VSS is inside the speedo, so replacement of the cluster with a used one is your best bet.

 

GD

 

He could have also snapped the speedo cable

Take your speedometer cable out and turn one end of it and make sure the other end turns, if it doesn't, you have a broken speedo cable, Same thing happened on my 91 but I didn't get bad mileage cuz mine was a 5 speed so it didn't go into limp mode.

Update: Okay, so I was tired of waiting for the new part to arrive at the dealer, I unscrewed out the adapter and I guess because of carbon/dust/sludge build-up inside the rectangle hole that the speedometer cable inserted into, the cable came out and wouldn't go back in. I forced it in a few times and then it went in smoothly afterward. I put everything back together and now my speed is working, but I continue to get terrible gas mileage. Last night, I took out the battery so the ECU resets itself, this morning, I continue to get very poor gas mileage. Does anyone have any more ideas where I should start checking on this culprit? I mean I could almost literally see the gas gauge moves! It's like the car is literally leaking somewhere, but no, there is no leaks anywhere.

Change the fuel filter, plugs, wires,air filter,pcv. Just small things to try in hopes of fixing the issue. Also try some seafoam in the tank to clean the injectors. Did you check what the code was???

Change the fuel filter, plugs, wires,air filter,pcv. Just small things to try in hopes of fixing the issue. Also try some seafoam in the tank to clean the injectors. Did you check what the code was???

 

Eventually, I will do them. And no, I didn't check the code. I disconnected the battery last night so the code was cleared. Does AutoZone have a code reader for the older (ODB1) connector? Most shops/stores just have ODB2 reader.

Eventually, I will do them. And no, I didn't check the code. I disconnected the battery last night so the code was cleared. Does AutoZone have a code reader for the older (ODB1) connector? Most shops/stores just have ODB2 reader.

 

You don't need it. Just use the procesdure here.

 

http://www.surrealmirage.com/subaru/subaru.html

 

Click notes and tips, then click engine related.

Can't see Notes or Tips.

Should be on your left side.

 

Wait figured out a way to give you a direct link.

 

http://www.surrealmirage.com/subaru/engine.html

Eventually, I will do them. And no, I didn't check the code. I disconnected the battery last night so the code was cleared. Does AutoZone have a code reader for the older (ODB1) connector? Most shops/stores just have ODB2 reader.

You probably didn't let the car relearn correctly. On the procedure page ericem posted, you'll note that after resetting the ECU, you need to put the car in park, start it and let it run(idle) for 10 minutes or until it gets warm then you turn it off. This process allows the ECU to relearn the car. I think this is a pretty important step - which you probably missed due to not knowing about it.

Another thing that can cause poor gas milage is a bad CTS, coolant temperature sensor. Also a leaky injector.

Just wondering...the guide says not to touch the gas throttle at all. I disconnected the battery overnight, but when I started the car, I push on the gas pedal, did I do something wrong by gasing on it? And by doing that, it didn't reset everything?

Another thing that can cause poor gas milage is a bad CTS, coolant temperature sensor. Also a leaky injector.

 

Excuse my acrynym un-knowledge, but what is a CTS? From experience with my Grand Caravan, a leaky FI usually makes it hard to start, is it the same case for most (if not all) vehicles?

The pedal should be left alone while the ECU does its' routine. You may have to redo the procedure.

 

The CTS is the coolant temperature sensor for the ECU. It is not the same sensor used for the temperature gauge in the dash. It is there for the ECU to determine what the engine temp is so it can adjust the fuel mixture correctly. One of the most common problems for bad fuel economy.

 

You are right about a leaky injector making the engine hard to start. The injectors are most likely fine but they are just another possible area of trouble.

I replaced mine and gained 2-4mpg was $20 sensor well worth it. Also take a look at your knock sensor ill bet its cracked if you haven't replaced it.

I mean I could almost literally see the gas gauge moves! It's like the car is literally leaking somewhere,

 

are you basing your conclusion of 'running crappy' on the movement of the gas gauge or on your MPG from gallons pruchased and miles driven. if you are using just the gauge, these guages are known for reading wrong (low). it could be mis leading you.

 

if on the other hand you are actually dividing miles driven by gallons purchsed, it may take a a little while to show your actual mileage. how many miles are you driving it on your test drives, 5 - 10 or 100 - 150?? more miles will give you a better idea of what is actually happening.

Does anyone know how different they look from each other? I called an auto parts store and the man said there is only one showing for coolant temperature sensor/sender. Are they identical to each other?