S1 - Intermittent Speedo

[AdrianR]

1998 Elise S1 - the Stack speedo has started jumping all over the place, going off for a few seconds then springing back to life again. Rev counter unaffected so I suspect either wheel sensor or wiring.

Q - Is there any way to test the sensor apart from replacing it and seeing if the problem goes away?

Thanks.

[Scuffers]

it's the sensor, or more to the point, it's spacing to the CV's trigger ring.

it needs to be ~1mm max away, BUT!

this could also be a sign of the wheel bearing wearing out, this le allows the CV joint to move a little in and out of range of the wheel speed sensor.

[kambites]

When that happened on my S2, it was just the connector between the sensor and the wiring loom. I sprayed it with WD40 and it's been fine ever since.

[Scuffers]

kambites said:

When that happened on my S2, it was just the connector between the sensor and the wiring loom. I sprayed it with WD40 and it's been fine ever since.

S2 totally different.

sensor is in the wheel bearing pack on them.

[kambites]

Ah. OK.

[AdrianR]

Scuffers said:

it's the sensor, or more to the point, it's spacing to the CV's trigger ring.
it needs to be ~1mm max away, BUT!

this could also be a sign of the wheel bearing wearing out, this le allows the CV joint to move a little in and out of range of the wheel speed sensor.

Thanks - actually that would be OK, as wheel bearing replacement is due anyway (at least one is noisy) plus ball joints and toe links. The car has been minimally maintained for the past few years so need to catch up on the backlog. Now jacked up with undertray off to see what else needs doing.

[dnb]

I had exactly the same symptoms on mine, and thought it was the wheel bearing too. It was the speed sensor itself.

It seems these are really hard to get now.

[Scuffers]

http://www.eliseparts.com/products/show/61/833/whe...

[dnb]

Sounds like that particular problem is finished. Do they actually have stock now?

[Scuffers]

dnb said:

Sounds like that particular problem is finished. Do they actually have stock now?

Usually, they pull stuff off the website if they have zero stock.

[AdrianR]

Hub now off. Feels smooth but some grease reside around the seal so will change it anyway. Sensor doesn't want to come out of its mount.

What wears out first? I did quite a few track days when I first got the car and it held up pretty well (normal tyres, no slicks) but I guess worth looking at some bushes and the toe link ends?

Might even get wishbones refinished, as they are starting to rust on the surface. Do people paint these, or get them replated?

• Edit - pressed send and then saw the other suspension refresh thread! **

Ta,
Adrian

Edited by AdrianR on Tuesday 24th March 18:56

[Scuffers]

AdrianR said:

Hub now off. Feels smooth but some grease reside around the seal so will change it anyway. Sensor doesn't want to come out of its mount.

having a trace of grease is not unusual..

what did it feel like when it was bolted up (as in with the driveshaft hub-nut tight?)?

and what does it feel like now in terms of pay (asif you try and twist the wheel side to side)?

[AdrianR]

I couldn't feel any play but there was a definite speed related drone coming from the rear.

OTOH, checking service notes that bearing (NSR) was changed quite a lot of years but not too many miles ago so maybe is sensor after all. Haven't looked at OSR rear properly yet.

Adrian

[AdrianR]

Speedo problem found - broken wire where it pivots round the wishbone.

[Mr E]

kambites said:

When that happened on my S2, it was just the connector between the sensor and the wiring loom. I sprayed it with WD40 and it's been fine ever since.

What were the symptoms? I have a working odometer but a suspect speedo. I'm concerned it may be the dash rather then something simple.

[AdrianR]

Speedometer needle intermittently flicking back to zero while driving, gradually getting worse until it was dancing about continually. Rev counter and dash otherwise fine.

Makes sense, the wire break was in a tight bend around the inner top wishbone pivot so everytime you go over a bump it would flex. Easy check on the S1 at least without dismantling anything much, just take the wheel off, snip vable ties, ease the wire from the "protective" conduit' and look for nicks in the insulation. Mine fell apart as I did this.

Now tackling the drivers side...someone convince me it isn't a left hand thread on the hub nut - I broke a 3/4 to 1/2 adaptor last night trying to undo it.

AdrianR

[Scuffers]

AdrianR said:

Now tackling the drivers side...someone convince me it isn't a left hand thread on the hub nut - I broke a 3/4 to 1/2 adaptor last night trying to undo it.

AdrianR

err...
no, they are all right handed!