Coolant temp sensor?

[Welshhobo]

57 plate 2.2TDCi 110hp

My temperature gauge on the dash has been dropping from 90°c to 60°c quickly when the van is running, and slowly making its way back up to 90°c again. I've replaced the thermostat (the old one was pretty rusty, but seemed functional), but still getting the same issue. I want to replace the coolant temp sensor but not sure where it is located - can anyone provide a picture or video demonstrating it?

The temperature drops pretty randomly but sometimes its when i hit a bump in the road. I get a small loss of power when it drops and a irregular hum from the engine when idling.

[knobby1]

57 plate 2.2TDCi 110hp

My temperature gauge on the dash has been dropping from 90°c to 60°c quickly when the van is running, and slowly making its way back up to 90°c again. I've replaced the thermostat (the old one was pretty rusty, but seemed functional), but still getting the same issue. I want to replace the coolant temp sensor but not sure where it is located - can anyone provide a picture or video demonstrating it?

The temperature drops pretty randomly but sometimes its when i hit a bump in the road. I get a small loss of power when it drops and a irregular hum from the engine when idling.

The Euro-4's don't have a coolant temp sensor, it's actually a cylinder head temp sensor and it lives in the cyl head between the fuel pump and vaccum pump on the FWD's...on the right side of the head as you look at it. You'll need a long series 15mm socket with a slot cut in to clear the wiring. These sensors usually fail completely rather than being intermittent. Could just be the loom or the connector not happy...worth checking at least.

Another thing to check on the FWD's with strange temp indications is the water pump drive coupling between the PAS and the water pump....it's quite common for them to fail and the pumps to stop turning...but this usually results in rising temps rather than the other way.

Lord Knobrot