Unintentional clocking……

[WHIPLASH]

My Speedo has become intermittent. After ten minutes of nothing it will suddenly start working and the mileage is doing the same.

I have only done 20 ish miles since it has started doing this and I believe it is to do with a sensor on the rear axel that may have been covered in oil after my speed bump incident.

I remember reading that this sensor needs to have precise measurements etc so is this a job for a TVR garage or can it be done by the average Joe?

Thanks guys.

[that daddy]

i had exactly the same problem after greasing the propshaft,turns out the prop had flung off the excess grease all over the stator causing intermittant operation,i cleaned the stator and sensor units......but guess what it was ok for a couple of weeks but as returned OH HUM,back under there i suppose.from what i can make out there not much tolerance between it working and not.

[paulathome]

Can be done at home if you have some axle stands and a jack.
Jack the rear of the car up and support with stands.
Crawl under the rear end and look up at the diff.
From your profile your Chim is a 1998 so the sensor will be mounted at the top O/S of the diff
housing. It looks like a big brass bolt which just misses the half shaft where the ABS (as used on the donor car) toothed wheel is. Check that there is no muck between it and the wheel. The adjustment is done by loosening off a
locking nut and then turning the whole sensor.
My advice would be to loosen enough to get a rag between the wheel and the sensor and give it a good clean.
Then reset the gap to about 9 thou' with feeler gauges. Do check however that the toothed wheel doesn't touch the sensor when spinning the road wheel on that side.
While you under there check the connector is ok and that the pins haven't pushed out of the back
of the plastic plug shell and then put a bit of sealant round them to stop water ingress.
Inside the car is a second connector that might be worth checking which is hidden under the centre console
right at the back. Black and grey wires IRC which come up through the floor just above the diff.
Hope that helps some.
Cheers.
Paul.

[Gaffer]

Had the same issue, had to replace the transducer (sp), it wasnt a big job anyways.

If you can clean it, then so much the better.

Claire

[that daddy]

i also found that useful Paulathome thanks,as i thought not much tolerance on that air/gap.

[WHIPLASH]

Thanks for all the responses. I love this Web Site, it's like having TVR experts who have been there & got the T-Shirt and none of the Bull S**t.

Unfortunately I have been requested to do some DIY in the house this weekend so I will let you know how I got on if time permits.

Thanks again guys & girls.
Whip

Edited by WHIPLASH on Thursday 12th October 08:34