darland

Active Member

• Sep 20, 2017

• #1

Evening peeps
Hoping someone can advise before I spend any more time and money fiddling with something I don't really understand. ..
97 auto disco 300tdi. Starts and runs fine but has recently developed following problem.; when starting warm/hot the revs momentarily shoot to 2000 then return to normal idle but check engine light comes on. Drives ok though. By process of elimination unplugging the water temperature sensor on top of head (the one for the egr) "resolved"
the issue so fitted a new sensor but problem persists. I could just leave it unplugged but I don't like something not working as it should - any ideas
please?

 

C

chris-the-gerbil

Well-Known Member

• Sep 21, 2017

• #2

Check the wiring to sensor isn't broken first....

 

darland

Active Member

• Sep 21, 2017

• #3

Thanks Chris, what conditions would I expect to see on the two wires?

 

Kwakerman

Well-Known Member

• Sep 21, 2017

• #4

If disconnecting the EGR sensor cured it then it sounds like it still has the EGR fitted and connected and it may be that causing the issue. Best solution would be an EGR removal (your engine will thank you!) but I don't know what effect that will have on the light (whether it will stay on)

 

darland

Active Member

• Sep 21, 2017

• #5

Yes that's on the list, any thoughts on what I should be testing for on the two wires leading to the water temperature sensor on the top of the head?

 

Kwakerman

Well-Known Member

• Sep 21, 2017

• #6

darland said:

Yes that's on the list, any thoughts on what I should be testing for on the two wires leading to the water temperature sensor on the top of the head?

Click to expand...

This should help you check the wiring from the sensor to the EGR ECU

 

darland

Active Member

• Sep 21, 2017

• #7

Thanks for that Kwakerman. I'm seeing 5v on the connector which I think is what it should be however the new sensor is not giving a reading on the ohmeter so now wondering if I've bought a Dudd? I was expecting to see a few ohms which change with the temp?

 

darland

Active Member

• Sep 27, 2017

• #8

Anyone?

 

Kwakerman

Well-Known Member

• Sep 27, 2017

• #9

If I remember I will try and measure mine tomorrow