p38 dse temp gauge not working

hello people. as per the title really, Where is the temp sensor located in the engine bay and is there any other things i should be looking for? I would feel alot more confident in driving my new rangie knowing i have an idea of coolant temps
thanks ..lee

leet said:

hello people. as per the title really, Where is the temp sensor located in the engine bay and is there any other things i should be looking for? I would feel alot more confident in driving my new rangie knowing i have an idea of coolant temps
thanks ..lee

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Look under manifold same side a FIP. It's the brown coloured one. The green one is for the ECU.

wammers said:

Look under manifold same side a FIP. It's the brown coloured one. The blue one is for the ECU.

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Thanks for that, i'll take a look

hey wammers, are you sure the blue coolant sensor is for the ecu? I have looked under the manifold and the only sensor i can see is the blue one which was unplugged. I have plugged it back in and now have a temp gauge readout on dash Cant see a second sensor under there. Its a 1997/R DSE if that means anything. Im happy ive now got the temp gauge working but want to know if this being unplugged has contributed to my current fuelling issues
Thanks ..Lee

I have the blue one unplugged.....when is plugged is very hard to start the car when hot.
(the blue one is almost under the electronic injector right? and the brown one near the injection pump? this one seems to have some sort of by-pass...)

Regards
Joao

jonasserra said:

I have the blue one unplugged.....when is plugged is very hard to start the car when hot.
(the blue one is almost under the electronic injector right? and the brown one near the injection pump? this one seems to have some sort of by-pass...)

Regards
Joao

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No my blue one is near to the rear of the injector pump. Couldnt see any others under there. I have a new starter motor and the hot start fix so am hoping it will still start OK when hot. Surely if you have unplugged the ECU coolant sensor, the ECU will always see the engine as cold and you would constantly be overfuelling?

Found this pic in the workshop manual.
Believe these are the sensors we are talking about...
The blue circle is the unplugged sensor in my car..(the Engine Coolant Temperature sensor)
(my DSE: 1998, manual, w/o egr)
About the unplugged one...the manual states that if the sensor is defective, ecu assumes a default value

hmmm, very strange. I wonder why my front sensor is blue? Anyone?

Probably because someone has put the wrong one in at some stage - assuming they have the same threads?

Derek Ward said:

Probably because someone has put the wrong one in at some stage - assuming they have the same threads?

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Surely the wiring plugs wouldnt be interchangeable though? I wonder if they output the same values

Hy Lee,

You're absolutely right.
Whent to check the plugs in my dse, the front one is blue, the rear one green.
Did you found the rear one?

...what fuelling issues you had?

jonasserra said:

Hy Lee,

You're absolutely right.
Whent to check the plugs in my dse, the front one is blue, the rear one green.
Did you found the rear one?

...what fuelling issues you had?

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look at my other posts recently. Basically i have had fuel starvation when needing power, i.e up hill. Cutting out at speed whilst decellerating and most recently overfuelling and engine management light. Whilst light is illuminated it just will not start. Ive been on the back of an rac recovery truck 3 times in the last month. Im frightened to move it again untill i have had a full diagnostics which is being done friday morning. Worst case, its going to be fuel quantity sensor which is internal to the injector pump and going to be big money
On a brighter note i have just got my old job back after 6 months struggling on by so will be buying an L322 TD6 very shortly and sticking a 2010 conversion on it

...i would go to a RR Sport Supercharged...

Could be the fuel pump in the tank?
Thought might be the injection pump....mine should be overhauled...as well as the injectors

jonasserra said:

...i would go to a RR Sport Supercharged...

Could be the fuel pump in the tank?
Thought might be the injection pump....mine should be overhauled...as well as the injectors

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ive done the in tank pump but this wouldnt stop it starting. It does look like it is going to be the fuel quantity sensor which is internal to the injector pump Will hopefully find out friday after the diagnostics. Ive been told my pump wont be worth overhauling as it has 200k miles on it

Hi, I have engine temperature giving me 3º C, with a hot engine.
It´s the "blue" or "green" I need to check/replace?
Thanks.

tomcatrr said:

Hi, I have engine temperature giving me 3º C, with a hot engine.
It´s the "blue" or "green" I need to check/replace?
Thanks.

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Are you sure its not the radio giving you the three degrees?

storm99 said:

Are you sure its not the radio giving you the three degrees?

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Can you explain better?
(3º C in Portugal, in August only in my fridge)
Ok, I found the value with a "testbook"

tomcatrr said:

Can you explain better?
(3º C in Portugal, in August only in my fridge)
Ok, I found the value with a "testbook"

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If you found that value on testbook your ECU engine temp sensor needs replacing. (The green one) Unless you have a faulty Hot start fix fitted.

Just for posterity. 2.5 DSE engine's sensors on head, in order from the front;
1 BLUE two pin if Aircon fitted, otherwise usually BROWN one pin, gives coolant gauge on dash board readings,
2 GREEN two pin sends coolant information to ECU.
3 sometimes fitted BLACK at the back for aircon fans.