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Water Temp Sensor?????

4028 Views 8 Replies 4 Participants Last post by  Secret Squirrel
I found this picture doing a search. Is the temp sensor in the diagram the same thing as the water temp sensor. If not, can someone tell me where it is? Thanks a bunch...Mike


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Hi Michael,

The B11/2 sensor has something to to with engine management. The sensor for the dash water temp indicator appears to be B13.

Cheers, MBL


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Sorry, I've got to get ready to go out with my wife.... now!

[:)] MBL
The sensor in your top pic is for the cold start injector, when it makes contact your injector fires. The temp sensor for the dash is the single pin on the thermostat housing. THe other is for the CIS E Sytem as part of it's input for adjusting the A/F ratio.

Hope that helps!

Michael - the injection system engine temp sensor is at the rear of cylinder head on left (drivers) side - it is connected by a green wire with a red stripe.

More info here:
Sorry, I was thinking M117 not M103..My bad for not looking:-/

I swapped this out today. You need a deep socket that fits the temp sensor. You also need to unbolt the engine pull bracket that sits at the very end (firewall) of the block - so that you can get to the sensor.

Pulled the old one out, a tiny bit of coolant ran out, then stopped, popped the new one in (with a new washer), hooked up the 2 connectors (doesn't matter which side they go on). The car fired up on the first try in 30F weather - NO way it would have ever done that before.

The new temp sensor had clearly been re-engineered compared to the old one. The sensor piece was longer and the connectors were green instead of black. So hopefully it won't die like the last one.
I looked and cant find it. I went to the back of the block. There is a bracket to the right (towards drivers side), a space and then the first firewall. Between the first and second firewall is a bunch of stuff including the Overload Voltage Sensor and the MAS. Is what I am looking for in the picture I attached????


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Ok in that picture, starting at the engine bracket on the driver's side of the block, the sensor is going to be the very first thing you run into on the block - hence having to remove the bracket while getting the deep socket on the sensor.

Big pic of the sensor:
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