Saab Tech Talk (STT)

Workshop for classic Saab models => Saab 9000 (1984-1998) => Topic started by: mikemusic on 16 September 2013, 01:30:36 PM

Title: Fixing speedo
Post by: mikemusic on 16 September 2013, 01:30:36 PM
My first post !

Hope you can help

I'm told that the only way to fix my speedo is to take the gearbox apart.
I can believe it, but I'd much rather have an alternative
My guy has spent a good couple of hours on it and he is good, although not a Saab expert
Anyone help please ?
Title: Re: Fixing speedo
Post by: sgould on 16 September 2013, 03:47:46 PM
Welcome! :)

I do believe that the gearbox has to come out and apart if the drive gear for the speedo has failed.  But I haven't owned a 9000, so I can't be sure.  There are experts around here that can help.

Just to give them a head start, could you tell us whether it's a manual or auto gearbox and what year the car was registered.
Title: Re: Fixing speedo
Post by: mikemusic on 17 September 2013, 08:46:58 AM
Thanks

Manual, P Reg, January 1997

Fingers crossed there is an easier fix
Title: Re: Fixing speedo
Post by: Kev_Mc on 17 September 2013, 11:13:42 AM
Welcome to the board :)

Not positive on removing the gearbox, though this chap suggests you do:

http://www.saab9000.com/gallery/yKLCYJAX/index.php

Removal and refitting guide - manual gearbox:

http://www.saab9000.com/procedures/powertrain/mantransmission/replace.php
Title: Re: Fixing speedo
Post by: wrighar on 17 September 2013, 07:38:13 PM
It may be the transducer on the top external part of the gearbox final drive (I had one fail, but the speedo would bounce up and down ot a crawling pace as one coil had failed).

But it's more likely the plastic gear ring has broken which requires a complete gearbox strip and rebuild....

Also, the car engine ecu uses that speed signal for itself and will start to degrade the driving experience/performance after a period of time (days/miles)

Title: Re: Fixing speedo
Post by: mikemusic on 18 September 2013, 08:04:32 AM
Thanks both
I was hoping for a magic fix. Seems like my guy Pete knows what he's on about even though not a Saab expert -Jaguar trained some years ago so he knows about problems !
Ironic that the gearbox was completely replaced just before I bought the car !

I cycle to work most days and rarely go anywhere. Running a printing company takes most of my time

Suggestions was that I get a GPS to give me speed indication

Thanks again. Time to ponder.
Title: Re: Fixing speedo
Post by: Kev_Mc on 18 September 2013, 08:58:17 AM
Quote from: mikemusic on 18 September 2013, 08:04:32 AM

Suggestions was that I get a GPS to give me speed indication


That's what I was thinking too - could a GPS be taken as a speedo for the purposes of the MOT?
Title: Re: Fixing speedo
Post by: ScarbSaab on 18 September 2013, 10:00:22 AM
I'm not a tester, but as much as I like the idea they would probably argue it is removable or not part of the car. If it take a while to get first fix or you go through a tunnel, you would be driving without a working speed indicator.
Title: Re: Fixing speedo
Post by: wrighar on 19 September 2013, 07:10:14 AM
Quote from: ScarbSaab on 18 September 2013, 10:00:22 AM
I'm not a tester, but as much as I like the idea they would probably argue it is removable or not part of the car. If it take a while to get first fix or you go through a tunnel, you would be driving without a working speed indicator.

And the car will start to run like rubbish after it hasn't had the speed signal to the ecu for a while.
Title: Re: Fixing speedo
Post by: mikemusic on 19 September 2013, 11:31:31 AM
Quote from: Kev_Mc on 18 September 2013, 08:58:17 AM
Quote from: mikemusic on 18 September 2013, 08:04:32 AM

Suggestions was that I get a GPS to give me speed indication


That's what I was thinking too - could a GPS be taken as a speedo for the purposes of the MOT?

I did wonder
Title: Re: Fixing speedo
Post by: mikemusic on 19 September 2013, 11:33:19 AM
Quote from: ScarbSaab on 18 September 2013, 10:00:22 AM
I'm not a tester, but as much as I like the idea they would probably argue it is removable or not part of the car. If it take a while to get first fix or you go through a tunnel, you would be driving without a working speed indicator.

I'll ask the question of an MOT tester I know - purely hypothetical of course !
:)
Title: Re: Fixing speedo
Post by: mikemusic on 19 September 2013, 11:35:12 AM
Assuming I get this done what else can sensibly be done while he's in there ?

Clutch comes to mind even though it seems fine, probably done around 30k miles