Hi, I've got a small problem with my sierra based fuel and temperature guages...

I'm using the original Sierra fuel sender and sierra instrument cluster. Both the fuel guage and the temperature guage read half full / half temp when empty / cold. and go off the scale when full / hot.

Any suggestions as to what might be causing this and how to fix it?

Thanks

there should be a voltage stabaliser for the gauges,knocks it down to around 9 volts

I think the voltage stabiliser is inside the instrument cluster (at least according to Mr Haynes it is).

I've been doing some work on my petrol tank today and the situation is like this...

If the wires are removed from the sender the meter reads empty.

If I connect the sender wires together the meter reads off the scale, same reading occurs when the tank is full.

When the tank is empty it reads half full.

???

this sounds like a miss match of equipment, its all to do with resistances of the senders.

It's all from the same sierra, same sender and same instrument panel, only the harness in between is different.

I'm inclined to believe it might be the voltage regulator as this is common to both fuel and temp guages.

Having said that though, if it was dead I'd expect it to fail to an open circuit rather than a short.