Speedo Dying/Irratic

[kerrinmay 0]

A couple of times, my speedo has just died whilst driving along, and then a few mins later comes back to life again, and also sometimes when driving at highish speeds it is semi-irratic and jumps between about 90 and 100mph and back.

 

Could this be the speed sensor? I've had a look at other threads on this matter but most seem to revolve around G60's, does the 2.0 16v have the same set-up?

[Yash 0]

I have a similar problem, except the speedo works but the mileage counter works when it feels too, it seems to only work once the engine is really warm, the mfa has died now as well. Think its time i bought some new clocks. :(

[Kevin Bacon 5]

Sounds like the speed sensor is dying and yep 16Vs have those too.

[kerrinmay 0]

Is it as easy to change as the other threads make out? How long should it take me? Any idea on current price of one?

 

Will I need to get it up on ramps or axle stands to get to it? Will be interesting to see if I can finally make use of my ramps, they weren't usable on my last car as the tyres were 225's and were too wide, hope the 195's will fit.

[Kevin Bacon 5]

Yeah it's pretty easy, just fiddly and awkward to get at. No need to put it on ramps, but 195s will fit on those though.

 

I think the speed sensor is about £30, or there abouts.

[kerrinmay 0]

Speedo needle was jumping all over the place this morning on my way to work. Wonder what people behind me were thinking as my spoiler was up and down like a yo-yo! Just as the spoiler started to come up the speedo would die and down went the spoiler, and then back up and down and...it goes on! Think I'll have to invest in a new speed sensor and hope that cures the problem.

[Supercharged 2]

Yep, I had the same problem, G60 sensor was £12+vat an fairly easy to get to and change... It's just on top of the gearbox...

 

You may want to check the wiring to it before hand as well...

[kerrinmay 0]

Don't suppose anyone has a photo showing where exactly I will find this sensor on a 2.0 16v?

[Henny 0]

It's in the same place as on a G60 box (they're the same apart from the gear ratios! ;) )

 

Look at the back of the gearbox and you'll see the bit where the driveshafts bolt onto. That's the Diff housing which sticks out there, and the speed sensor is the ONLY bit which sits on top of the Diff and has wiring going to it... ;)

[kerrinmay 0]

How much wiring is there on a speed sensor? Will I have to trace the wire back to the actual speedo etc, or is it just a matter of unplugging the sensor where it is and plugging in a new one?

[Henny 0]

it's a plug and play jobbie... Nice and simple. Unplug the old one, undo the bolts holding it into the gearbox (2x 10mm headed bolts IIRC) remove (carefully!) the old one and replace with the new one... 8)

 

I've not done one of the electronic ones before, but I have a feeling you may have to change the drive gear over from the old unit to the new one... can anyone confirm this?

[Supercharged 2]

it's a plug and play jobbie... Nice and simple. Unplug the old one, undo the bolts holding it into the gearbox (2x 10mm headed bolts IIRC) remove (carefully!) the old one and replace with the new one...

 

I've not done one of the electronic ones before, but I have a feeling you may have to change the drive gear over from the old unit to the new one... can anyone confirm this?

 

You just unscrew the plastic bolt you can see which is the sensor itself and unplug the connection at the top (err, maybe unplug it before unscrewing it!)

 

You may need a large adjustable spanner if its tight but I managed to do mine by hand.

[Henny 0]

oh, easier than I thought then... 8)

[Supercharged 2]

Ok here it is - the nut is actually 22mm and the plactic bit you see it the centre of it locates into the spindle that comes out the gearbox (it spins it round to generate the signal) - just make sure you locate it centrally before you screw the new one down, simple!

[kerrinmay 0]

Thanks. So can I confirm it is just a sensor, and I've not got to run wiring anywhere? How long should it take me to change this sensor?

[Supercharged 2]

No, you just unplug it (see the plug on the right of pic) then uncrew, should take 5 mins.

[kerrinmay 0]

Replaced speed-sensor yesterday, and it was as simple as it sounded! Took no time at all, apart from waiting for the rain/hail/snow/wind/thunder to subside! Touch-wood, it seems to be ok now, but will need to give it a few days as it didn't play up every day.

[Supercharged 2]

8)

[kerrinmay 0]

Still seems to be working fine, and strangely enough (touch-wood), my cutting out at idle seems to have stopped! Thought this was an ISV problem but could it be that if the speed sensor was misbehaving that it could affect the idle - from the point of view when it fails to catch when you drop it out of gear and it just cuts out?

 

Thinking back, the cutting out did tend to start happening just about when the speedo started playing up, but I thought that was just a coincidence.