Thank you for the information. I have tried to find the sensor and have to admit that I cannot even find the thermostat housing. I followed the lower rad hose back to the engine thought its convoluted path: under the intake air duct; under the distributor; under the turbo air duct, and to where the rad hose joins a metallic pipe leading to the passenger compartment side of the engine.

How much of this stuff do I need to disassemble to get at the thermostat housing and locate the sensor?

I would just like to get at the connector to measure the resistance of the sensor when the engine is cold, and then again when it's hot. I believe that it is causing the difficulty in starting the engine when the engine is hot.

Also, my Datsun has two sensors, one connected to the computer module and one for the instrument panel indicator gauge. Does the 850 have one or two sensors? (I ask because the temperature gauge indicates the temperature properly.

Again, my thanks for any help on this issue.

Ofer