Thread: New project 89 vogue

Originally Posted by Rick1970

As said, check wiring to the coolant sensor on the LHS of the inlet manifold. Also check its resistance vs temp, from memory should be about 300 Ohms at operating temp???



They run terrible when they go kaput, and new ones are cheap.

The operation of the temp sensor affects the engine running? I thought it was just for monitoring purposes. Will have a look!

There should be two, LHS top/front is for the ECU only. RHS front with single wire if for the gauge only.

Plot thickens. So I see a temp sensor on thermostat housing. 2 pins.

Seems to be the thermostat housing fan switch. PRC3505

Next up there is a single wire temp 'transducer' on the left of that. PRC7918


Now where it gets interesting. On the passenger (LHS?) of the inlet manifold there appears to be 2 coolant temp sensors. ETC8496

I may have the plugs swapped around? Why are there 2? Will keep looking.






I had brown plugged into brown I think. Who knows what is right though...

That's what it's meant to look like. Why would there be 2 senders...

As I am buying some brake lines for the other RRC any way, figured I will chuck one of the temp sensors on order - only $8.50...

The brown plug has blue/purple and red/white wires.

The yellow plug looks to have black/white and black/grey wires.

Cannot find anything on the wiring diagrams about a temp sensor.

Have been thinking the second sensor may be related to the gas system.

Visited old man who has a 88 wreck that was also on gas, and yes it has the second sensor:


One thing I spotted though, on mine there was a 'spare' injector style plug after putting everything together.
Here it is plugged in on the wreck:

It's the black one bottom right. This may be causing some of my issues.

It's the auxiliary air valve

The extra sensor is the thermotime switch for the extra cold start injector. This is disconected in mine. It's likely it may cause a running problem if the plugs were on wrong.

Think the plug to the back of the extra air valve just supplies a voltage to the heating coil in it, could be wrong tho.

The diagram you posted would be for a Hotwire injection system I think, the last pics are an earlier flapper style. These have the thermotime switch and extra air valve, later Hotwire systems do not.

In any case, number 21 is the temp sensor for the ecu, and is worth replacing.