Sensor on RR Hub

[jkorvette]

What is this sensor mounted on right rear axle hub for on my 1989 Esprit Turbo non-SE?

Thank you in advance for any insight.

Jkorvette

[Gjk]

It is a wheel speed sensor. If you upgrade to a forum member you are entitled to get the parts manual for your car as part of the subscription. I found just the part manual alone taught me a lot about the esprit.

[jkorvette]

Thank you Gjk for your reply. Is this wheel sensor standard and what does it control?

 

 

[snowrx]

Usually ABS brakes, but sometimes a manufacturer will get vehicle speed direct from the wheel. I don't know the specifics for your car. Wiring diagram may show which module it connects to.

[Escape]

The 1989 Esprit didn't have ABS (many would say luckily 😉 ). That's why it's only the one sensor, for ABS you need a sensor on each wheel, like the later Esprit. So it's just for vehicle speed. Funnily enough, the actual speedo is still mechanical with a cable drive from the gearbox. The speed reading from the sensor is used only by the engine ECU. But it can be used to drive an electronic speedo as well.

[jonwat]

6 hours ago, Escape said:

speed reading from the sensor is used only by the engine ECU

Does a 1989 Esprit Turbo non-SE have an ECU?

[Escape]

The Turbo S should have the sensor, as it's basically the same ECU as the SE. I'd say the carbed turbo and Bosch turbo (NAS) wont have a sensor, but can't confirm.

[Barrykearley]

if that car has an ECU that does the fuel in so you will need it

[Escape]

Not quite, if there's an ECU, it should have a sensor, but it will run perfectly fine without it. So you don't really need it.

[Barrykearley]

On the S I had - I can categorically say it made a difference to fuelling on boost.  When the sensor was bad - it held back a fair old bit.

[Escape]

I stand corrected, I thought it was only on the later models and V8 that boost was restricted at low speeds. If the S does indeed limit boost in relation to vehicle speed, running without the sensor will be possible but you'll miss out on some of the fun. 😉

[jkorvette]

This car is a 1989 Turbo S with ECU I believe, no charge cooler with Delco injection.

[Escape]

That was our assumption based on your original info and photo. 😉

So it's the speed sensor for the ECU. You can always try to unplug it and see if it makes a difference on boost.