ECU water temperature sensor

[NiaLaurie]

We have a 1994 4L pre-cat Griff. Recently it started running badly, backfiring etc. I got my usual mobile mechanic in and it was clearly over-fueling - soaked plugs etc. Suspicion fell on the ECU water temperature sensor so we disconnected it and like magic the car was running perfectly.

I will replace the sensor but does anyone know the ECU default when it sees a failed sensor? Its tempting to leave it as it is!

Thanks

[nawarne]

I'd try doing a search on here.
Seem to remember many posts regarding re-siting this sensor. The TVR chosen position is in a "dead-spot" for coolant flow - -yet the original Rover position ensured that the sensor was in a much better position for giving a representative reading.

I'm no expert, but I'd say the ECU will rely on the measurement of the coolant temp' to provide a richer mixture for cold starting....Therefore I reckon you should get a new sensor and re-connect.

Nick

[andrewbr]

The badly positioned sender is for the gauge only, the ECU sender is in a good spot on the intake manifold, next to where people swap in the Range Rover/Caterham sender for the gauge.

[davep]

The 14CUX ECU sets a default engine coolant temperature value of 36° C if a fault condition is sensed (sensor voltage out of range). This has an impact on many fueling functions, including:

- when to go into or out of closed loop, not so important for a precat
- hot and cold engine start up or cranking strategies
- engine warm up
- idle control, when changes in temperature are critical
... and so on.

Running the engine with a fully functioning ECT sensor is probably the best option.

[NiaLaurie]

Thanks all.

I will be installing the replacement as soon as I get it.

[NiaLaurie]

Thanks all.

I will be installing the replacement as soon as I get it.