legacycentral bbs

I recently picked up a nice and clean 91 Legacy wagon for $400. The compression is great - no leaks or crud under the hood, overall good shape. But there was no speedometer cable. I just put one in, but the speedo (and odometer, cruise, etc) still don't work. The ECU, once I found it, flashes 33 for the speed sensor. Any ideas on where to look next? I'm not very familiar with Subarus yet.

First thing you should check is to see whether the cable and speed sensor in the combination meter are working. Yeah the sensor is in the dash. Take a drill and have someone turn the speedo cable a little bit....in both directions to make sure it's working. If the needle moves....then the base piece is probably broken.

I've got a thread where I talk about it more, but here is the pic of the piece in question
http://www.main.experiencetherave.com:8 ... lebase.jpg

Thanks for the tip. The cable came with a new base attached like the one in your picture. I unscrewed it from the transmission and connected a drill to it while my sister sat inside the car. It did go up -to 75mph- with the drill. So I guess this means that the problem is in the transmission somewhere?

I think it may be a 1990, and not a 1991, model.

hmm.....if it's in the transmission itself....the plastic gear is busted.....and they're not easy to fix without taking apart the tranny.

Thanks, it is the plastic gear. A $12 part that costs 620$ to put in (dealer). Has anyone made a servo-unit to bypass this gear, but still turn the speedo?
And does anyone know what the tach should read at 70 with a 4eat?

in 2nd gear probably around 6000

Isotopeman,
I have 1994 RHD Subaru legacy L station wagon and my speedo doesn't work.

I was just curious if you had this speedo gear problem fixed yet. Have any thing to share? I have attempted once and it seemed to have a problem with the speedo gear. My odometer is also stopped registering. Is this all related problem or know anyway to make the odometer to work, at least?

Thanks for your time!

Hello DonQuixote,
I haven't had the speedo problem fixed yet. It's simply too expensive to have someone do the work. A friend and I are working on a servo-unit simply to turn the cable the right speed based on wheel/axle rotation. It's been slow-going though while it's not a top priority. I don't drive the car too often. The problems are related - odometer and speedometer. There's also a problem with the ECU missing the signal from the speedometer (trouble code 33). It's been explained to me that this will even make the engine run a little rougher. These guys here know quite a bit more than I do, and somebody will probably be able to provide a better answer soon more specific to your car. It seems to be a common problem though.

Thanks for your reply!

A friend and I are working on a servo-unit simply to turn the cable the right speed based on wheel/axle rotation

I just might have to do the same thing until I can get my speedo fixed.
I don't even know what a servo-unit is, but is this something that can be done easily?

Could you post any of your progress you are making with your servo-unit? I am sure that there would be many of us who could benefit greatly and personally, I would be very interested in hearing more about it!

Thanks for your time and have yourself a great weekend!

oops. Too many things at once. We hope that a step-motor would work. The driver's output would be based on something like pulses from a magnetic sensor - like the kind that the bicycle speedometers use. Say that you put a magnet on the driveshaft or wheel somewhere with the sensor fixed, every time the magnet passes the sensor, you know that you will have traveled the circumference of your wheel (compensating for pressure, etc - just measure the distance on the ground if needed). Calibrating the driver for the step motor may be the trickiest part. Anyone else have ideas about something like this? Definitely cheaper than tearing the transmission apart.

You have to know the motor parameters first, like the degrees/step, acceleration speeds, etc. What kind of controller are you using? To be really clever, you could run it off a PLC and download different programs for various wheel diameters. I wass doing a project like this at work with surplus parts for an indexing axis on a wave solder machine, but due to various reasons was never able to complete it. One big problem was getting all the motor parameters from Pac-Sci. It can be a pretty complicated job.

Steve

True. It has been a problem finding all the specs on motors available. For the controller, we were looking at these little computers with 16 input/outputs. My friend has used them for other projects. A simple program can be written on a pc, then loaded onto the computer. What makes a step motor so attractive is the idea that the gear in the transmission would turn a certain number of degrees per revolution of the axle. But finding that specific information would be a luxury. Step motors are also expensive though. Which would defeat the purpose of skipping a repair of the transmission gear. This is not really in my field of expertise though. My degree is in German - mostly literature.

It can be pretty complicated. You may be able to find surplus motors cheap, but getting the specs on what may be a discontinued PN may be difficult. Programming can also be a PITA if you've never done it.

Steve

So how difficult would it really be to put in a manual transmission? A friend of mine offered me her Audi A4 for a few weeks, and it has made me miss the standard transmission. If it's going to be too difficult/expensive to fix this, maybe a used replacement would be cheaper?

So far I'm believing that a 4eat-5mt swap is more expensive and more complicated than just a tranny swap. Unless you have a donor car you're going to be searching all over for parts. It's the little things that you need to get that you wont find unless you've got a donor or go to the dealer :\

THAWA wrote:So far I'm believing that a 4eat-5mt swap is more expensive and more complicated than just a tranny swap. Unless you have a donor car you're going to be searching all over for parts. It's the little things that you need to get that you wont find unless you've got a donor or go to the dealer :\

Bingo!!!! ding ding ding....Jonny...tell him what he's won.

Seriously though....yeah it'll be cheaper in the long run to find a donor car.....it's why I went the route I'm going.