Amazingly well documented Odometer Fix

Post by **stone36** » 12 Jul 2008, 12:37

Thanks for all the pics and advice so on this topic. Just finished and just like everyone said, about 2 hours.

One thing to add if you are looking at doing this, when you get to the step of removing the actual odometer unit there are three screws on the back that you have to take off, they are philips head and the top three in the picture in triangle shape.

The two screws on the bottom the instructions said to remove, but I found I didn't have to.

Also is this warping on the back just from heat, does everyone else's look like that?

Thanks guys!!!

Bruce in Georgia · Post by **Bruce in Georgia** » 20 Aug 2008, 06:14

I'm totally new to this forum, and this odometer section is fantastic. Here is my problem - my odometer and trip meter quit for about 50 miles. Then, started up again. Ran another 200 or so miles, then quit again. Now, I drive 10 miles more, and they both are working. Huh?! I have a 93 850, so the moving wheels in the odometer certainly would be mechanical, but before I attempt any fix, how could a broken gear as has been described in this odometer section be the problem? It sounds like an intermittant issue, but I was wondering if anyone has ever encountered something like I just described? What is the next possible problem if it is not a gear?

Any help would be greatly appreciated.

Post by **Ozark Lee** » 20 Aug 2008, 06:53

We've had a few members that have had similar experiences but their odometers craped out completely in short order.

It could also be a problem with the vehicle speed sensor or its wiring. Check for codes in port A-7.

Normally an actual fault in the speed sensor will cause problems with the transmission.

...Lee

Bruce in Georgia · Post by **Bruce in Georgia** » 20 Aug 2008, 07:33

Lee,

Thanks for the information. It is interesting to note I have seen a random and sporadic drop in RPM's and power when I'm at freeway speed and my cruise control is on, so your comments on the speed sensor might be connected. I am not, howver, getting any check engine lights on, and wouldn't a bad speed sensor cause those lights to come on? I see in another speed sensor thread there are actually two sensors - on connected with the transmission, the other is a Vehicle speed sensor. I'll check out the codes for the A-7 port and see if that indicates one or the other. Thanks for pointing me in this direction. I had already ordered one of those tiny gears to the odometer, so I may be going that route eventually, but because the sensor sounds more logical than that small gear not working (the odometer would not be able to turn at all if the gear was shot, right?), so I'll go that route first. Thanks again, if I get results that are worth sharing I'll do that.
Bruce

Audis2vato · Post by **Audis2vato** » 25 Aug 2008, 10:33

I have found this site helpful and very no-nonsense not like some Audi oriented sites I have had to deal with. The Odometer fix is fantastic and with accompanying pix, the ultimate owners heaven sent. I am about to undertake this fix and have some questions.
1. Is it sound logic to replace both the large & small gears?
2. How hard it is to remove these gears? Are they glued on? Pressure fit or just sitting on shafts?
4. How hard is the plastic cover pressed on? Should I use a plastic scrapper to remove it?

Post by **Ozark Lee** » 25 Aug 2008, 12:44

I have purchased both gears for all of my 850's. I have a couple of the large gears leftover that were good but I don't know how long they were going to stay good. They all showed some signs deterioration with the plastic getting somewhat gummy.

The gears aren't even pressed on. They ride on shafts and they can be removed with no force at all.

The faceplate requires a fair amount of force to get it separated, I've found that walking it off from side to side helps. If you have a turbo you also need to remove the brass nut from the boost gauge nipple. I just use a straight slot screwdriver to get them apart.

Before you pull the faceplate off snap a picture of the gauges. The zero resting positions on the gauges wants to change as it gets jostled around and you need to get them back to their previous positions or the gauges won't be accurate. I re-zero them by manually running them to the far and and then letting go of the needles. It may take a few tries before they re-settle at the proper zero position.

...Lee

Jibboo · Post by **Jibboo** » 02 Sep 2008, 08:33

Hi. Great write-up on the Odometer fix! Very easy to follow.

Before the repair, I used the pencil method with the old gear to correct the mileage.

I made the repair with the new gears.

Put it all back together again. Drove it home (about 4 miles) all good. Drove it to work this morning, after 10 miles it stopped working.

Will be tearing it apart tonight and hopefully fixed to get it in for inspection tomorrow.

Any ideas why it failed? And how to fix correctly?

Unfortunately PA requires an operational odometer for inspection. I still can't figure out why. The ironic part is, the speedometer does not need to be operational to pass inspection. I don't get it. I thougt the point of inspections were to insure the safety of the vehical to be on the road. What does the odometer have to do with the safety of the vehical? Doesn't make sence.

Do the new gears need to be greased or lubricated at all?

Any how, please let me know of any fix or something I could have missed in the process.

Thank-you.

Once again, this is a totally awesome website!

Looking into getting a draper tool for the service light.

Jibboo

Post by **Ozark Lee** » 02 Sep 2008, 08:44

There are two versions of the odometer motor, one type has a wire pigtail that plugs into a connector and the other style has the a connector that is mounted on a PC board. With the latter style it is easy to not have the motor plugged in all the way. That is where I would start.

...Lee

Jibboo · Post by **Jibboo** » 02 Sep 2008, 08:50

Thanks Lee,
I do have the PC-board type.
Won't be able to get to the car until this afternoon (after 4pm ET). Will log in then again once we are looking at it.

While I am at it, might disconnect the service light and solve that problem that way. It's annoying and dealer is a bit rude about re-setting it for free.

Thanks for the response. I see your name on many posts in here. Thanks for taking an active participation in the forums!

On a side note, I saw a post about a DIY for the ABS module computer. Not sure I want to tackle that one myself. I see ebay offers for around $100-$140. Sounds like a deal. Any ideas?

Jibboo

Jibboo · Post by **Jibboo** » 02 Sep 2008, 16:48

Lee,

Rushed home after work.

Tore the dash apart, had it all taken apart, took apart the gauge cluster, put it back together again, and all back into the car in about a 1/2 hour.

So, once you do the fix once, it takes about a 1/2 hour to do it a 2nd time.

Drove it to the Dealer to drop off for inspection. About 6 miles away and the odometer ticked off the miles accordingly.

Anywho, it should be good enough to pass inspection now. If it happens again, not sure what I'll do. Probably will just let it go until next year. Until then, I am never going to press the odometer trip button. I believe that is how the gear busted.

Of course, I ran out of time to check any other system, exhaust, brakes, etc. Have about $600 worth of new Michelins on it, did that before I did the odometer fix. At that time, I didn't know about the odometer needing to work. The tires would have failed inspection anyways.

Any ideas how to get better gas mileage from it? I run 91-93 octane (what ever the high grade is at the time of purchase). It's a '97 850 GLT wagon, Turbo. I keep the oil changed. Keep the tires up to snuff. Get between 21-23 MPGs mostly highway, 65-75 MPH. Would like to get as close to 30 MPGs as possible. (I drive about 30 miles one way to work each day). The person I bought it from was an old time Ferrari/Jaguar Used Dealer/Mechanic. He was inserting a little fan type device into his air hoses going between the filter and engine. Supposed to boost horse power and MPGs like 1-10% or so. Didn't know if anything like that was recommended for a Volvo, let alone a volvo with a turbo. Many people on here only recommend standard air filters, and they say the K&H high end stuff clogs and damages the car after a while. How do the R series get more horsepower? Possible to incorporate anything from an R to help improve gas mileage on a GLT?

I plan on dropping some change into the till here after I find out the damage from Volvo Dealers inspection. Money keeps disappearing and the beer keeps running short. But once I get it back and pay off the credit card, I'll be happy to make a donation. Also, want to keep accessing the site anyway. Want to fix the ABS computer, and do some other stuff.

Thanks again,
Mark