190E 2.5 Cosworth Temp Sensor

[BoB H]

Hello all,
I think I have a problem with this, 4 pin,thermo timer/temperature sensor. Apart from substitution, is there a way of testing this i.e. via d.i.y.
multimeter. Your replies will be much appreciated,
BoB.

 

[Stevie A]

The resistance figures for this are in the Haynes manual:
At 80 degrees C 325 Ohms
At 40 degrees C 1200 Ohms
At 0 degrees C 6000 Ohms

Measure across the pins diagonally I think.

This is for the Bosch CIS-E KE-Jetronic fuel injection system. Section 4B-2 in Haynes.

 

[television]

Hi bob, yes it can be tested on a multi meter, I have not seen the 4 pin versions

I will see what I can find

 

[Stevie A]

Hi bob, yes it can be tested on a multi meter, I have not seen the 4 pin versions

I will see what I can find

Hi Malcolm - I just put that up at the same time as you.

To Bob, What are the engine symptoms anyhow? What makes you think temp sensor is faulty?

 

[BoB H]

Thanks Stevie,
I posted a couple of times regarding starting/tickover problems.
The outcome being,new OVP relay and new rotary idle valve fitted.Both making some improvement but the main problem now is being unable to get tickover below 1000,unless the feed to the control valve is removed;making it seem the "message" from the sensor may be wrong. There is also a problem of stalling when selecting gears,may be related but until tick over is correct this problem can't be diagnosed properly. Hope you can follow that!
BoB.

 

[television]

1k rpm would indicate that it is running on the main ECU and not the idle circuit

 

[BoB H]

Thanks Malcolm,
a further comment/query on the sensor:- would it be logical to think that if everything is o.k., removing the plug from the sensor when running (hot or cold) should make a difference; either faster or slower? Or doesn't logic really work on this sort of technology? What do you think?
BoB.

 

[television]

Thanks Malcolm,
a further comment/query on the sensor:- would it be logical to think that if everything is o.k., removing the plug from the sensor when running (hot or cold) should make a difference; either faster or slower? Or doesn't logic really work on this sort of technology? What do you think?
BoB.

for 99% of the sensors, if you remove the wire, it will thinkl it is cold air and cold water temp, in other words the resistance is high when cold going down to almost zero when hot, so by grounding the wire it will think it is warm air and hot water