Engine Temperature.....1.6TD

[GrahamL]

Hi,
I have now have my van on the road for a couple of months after extensive work on the body. Now completing two relatively long trips of 120 and 150 mile round trips, significant town driving now totalling in excess of 550 miles.
I have had a service and a good overall look around the brakes etc.
During the time in the body shop I had a suspicion of mechanical issues, one of which was engine cooling. I checked the temperature gauge and found when the circuit was linked out it registered and moved across the full scope of the gauge.
As part of the service I asked the garage to investigate the engine cooling issue. They replaced the sensor. On receiving the van back and driving approximately 10 miles the temperature gauge hardly responded almost no difference to when I left it with the garage. I returned to the garage, they suggested being a diesel, it will take a long time for the engine to warm up.
After now completing in excess of 550 miles there is no change, the needle if at all does not move off the bottom of the gauge. If it does only by a millimetre.
Is this normal as suggested by the garage ........any help will be appreciated.
Regards
Graham

[lloydy]

No its not normal, most vans the needle will hover over the led which is centre of gauge. 1st thing to check is whether the thermostat is actually working, if this has failed it will allow circulation around the radiator all the time and the engine will run too cool. So, start the engine, maybe take it for a very short drive around the block or just increase the revs for a bit on the drive and check if the rad gets warm. If it does then the stat has failed and a new one is needed.
If that all checks out ok you need to start checking the wiring like poor earths, and maybe even check if the garage changed the right sensor on the engine.

[GrahamL]

Cheers lloydy,

I'll have a look at this.
I have the Bentley manual, but cannot locate the thermostat housing......if this requires replacing!
Looked in Wiki and checked out the diesel engine bay photo!!!!
Regards
Graham

[lloydy]

its on the back of the water pump. its not a housing as such, just a plastic elbow.

[GrahamL]

Lloydy,

Again cheers for this...........as the van has had little use ( yards back an forth in and out of the Bodyshop....this is another story) over the past couple of years; as a matter of course I'm thinking about changing the thermostat.
Regards
Graham
This would not have an influence on oil consumption by anyway?
Regards
Graham

[lloydy]

wouldn't effect oil use at all.

[clift_d]

Sounds like a connection issue to the sensor they replaced - check that the wiring has been connected up again, and clean the contacts.

[Joncorry]

I have exactly the same problem with my JX following a head gasket failure. The needle on the gauge hasn't moved since. I'm going to order a new sensor and swap that first. The led flashes on start up then stops after a few blinks so at least I know that is getting power.

[Timburrows]

If you remove the sensor wire and earth it the gauge would go to very hot end of the scale and the light will flash,this will only test the electricial side of it gauge wire etc,the sensor you could swop temp and heater temp wires over,this would make your heater plug light come on even when the engine is hot but your temp gauge should work correctly IFthe sensors failed,if everything is still the same then thermostat should be looked at.the testing should save you time and expence.changing the thermostat you should test it in boiling water to check it opens before fitting,could save time and effort later!