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Discussion Starter · #1 ·
Having sorted my clutch problems another small anoyance has gotten worse.

A while back i mentioned that my temperature gauge was reading at about 8 O'clock, where it used to read at 9 O'clock, it now just about gets to the top of the blue mark.

I was going to measure the resistance of the probe to see if it is obviously faulty, trouble is, there are so many hoses etc on the inlet manifold i cannot tell where I'm supposed to measure!

Can anyone help

Skiddins
 

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As the resistance of the sensor goes down as it gets hotter, underreading could be caused by excessive resistance in the wiring/sensor (or it might just be a thermostat stuck open and the poor engine not getting hot enough).

The sensor is (on my MY94 at least) on the head not too far from the thermostat housing (back or side, I can't remember) and has a single wire going to it. It might be worth pulling the connector off, cleaning everything up and ensuring a good contact between lead and sensor. However, a thermostat problem would be more likely in my view.

Start the engine from cold and keep your hand on the top radiator hose. If it gets warm quite soon, rather than suddenly hot as the thermostat opens, that's the problem.
 

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Discussion Starter · #4 ·
After fiddling with what i believe to be the connector (the transducer is in the battery end of the cylinder head right below one of the water pipes going to the turbocharger) which is lying below the throttle body, i have managed to get a range of temperatures from 'stone cold' to 'just right'.

So I'm sure it is the wiring somehow, but i couldn't seem to get the connector apart, It has two wires and i could just about get both hands to it.

Should it be a spring release or something, it's very hard to see clearly.

Skiddins
 

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Mine's got very similar problems. I also get the 'check engine' message in the dash relating to it as well (intermittently)

I was thinking of doing something similar to Skiddins. Just to be sure does anyone have a photo of exactly where the sensor is?
 

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I noticed two sensors on my car, one with two wires and a Bosch style spring connector, the other a single wire with a bare spade (Lucar) connector onto a sensor with a mushroom shaped head.

I'm guessing that the double wired connector is part of the Trionic system, and the single wired connector supplies the gauge signal, but I'm not sure. No doubt someone more knowledgeable will be along soon........
 

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Discussion Starter · #8 ·
The connector i saw had two wires, it appeared to be the only thing wired into that end of the engine.

If you follow the main coolant hose from the radiator to the engine (battery side of engine bay), this is where the thermostat is, though it is mounted at a strange angle.
Below the hose on the side of the engine about 4 inches down, there is a mushroom shaped component screwed into the side of the engine with two wires coming out, this appears to be the sensor, at least, when i tried moving the wires etc the reading changed.

Skiddins
 

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the guage wire is normally the uninsulated lucar connector which pushes onto a mushroom headed sensor screwed into the location you are talking about..... if you have waggled things in that area the chances are you have disturbed that wire aswell. if you can find it then give it a clean and close it up a little with a pair of pliers then pusit back on. I am not that familiar with trionic cars but i would guess that the guages all work pretty much the same
 

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The temp guages changed when they moved management systems: My 93 has a single mushroom top temp sensor with a spade connector pushed over it. My 97 has a twin wire connector and yes it reads odly - I had a new thermostat in and it cured it for a while and then started sulking again.

My concern was, and is, that the engine management, might be getting the wrong engine temp and so it would be using the wrong fuel mix.

Steve
 
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