Temp Gauge Reading

[SoCal Driver]

OK, I'm becoming a real pest to the local dealer. I buy $20 worth of odds and ends then ask $300 worth of questions.

Here's what I've just walked away with, the ohm readings for the temp senor, oil pressure and fuel tank for most 944s.

Up to the 85.5 where the temp gauge is at the top:

40 C = 287.4 ohms
105 C = 33.6 ohms
120 C = 22.7 ohms

This may be the small single connection brass fitting behind the throttle body on the block. Threads into a blind hole and does not contact the coolent. Clues?

See included graphics for locations on gauges.

After the 85.5 where the gauge is on the side:

40 C = 287.4 ohms
60 C = 134.0 ohms
80 C = 69.1 ohms
100 C = 38.5 ohms
115 C = 25.8 ohms

Think this is the DME type senor in either the oil or coolent. Any clues here?


Also have the resistance values for the fuel tank and oil pressure gauge/senders if anyone wants them.

[951carter]

That would be a nice addition to the 944 FAQ. I don't think anyone has taken the time to do that before.

[AFJuvat]

The location of the temperature sensor for the coolant is located right above the upper balance shaft housing, There are two temp sensors there.

If memory serves, the one closest to the front of the engine feeds information to the temp gauge on the instrument cluster, the one right behind it feeds temp informaiton to the DME.

They both read the temp directly from the coolant, right before it is returned to the radiator

AFJuvat

[SoCal Driver]

Originally posted by AFJuvat
The location of the temperature sensor for the coolant is located right above the upper balance shaft housing, There are two temp sensors there.

If memory serves, the one closest to the front of the engine feeds information to the temp gauge on the instrument cluster, the one right behind it feeds temp informaiton to the DME.

They both read the temp directly from the coolant, right before it is returned to the radiator

AFJuvat

Au contraire, The little brass single pole (looks like a miniture radiator fan unit!) does not contact any coolant! It's a blind hole tapped 1/8 FPT. Has a slip on connector like the instrument wiring. This sensor is furthest from the timing belt cover.

The other sensor, about 2" overall length does contact the coolant and does have the same connector type as the rest of the DME harness.

Now on the 86 engine there were (engine fire) two sensors with the DME type square connectors. One into the coolant and one into the oil galley. The furthest away from the timing covers is located where the little brass one is on the 83 AND the hole is bored through to the oil galley. There are two bosses here side by side. I've blind drilled and tapped the second 1/8 FPT and screwed the little brass sensor in. Left the melted one in the oil galley.

Puzzling...