2.2 Hdi Glow Plug Light And Temp Sensor

[chunkymunky1988]

Hi all. When I turn my ignition on the glow plug light will stay illuminated for quite a long period of time before it goes out, maybe 15 seconds and then when I start the car it revs high for a second or so and sounds rough until it's heated up then it starts no problem and the glow plug light goes straight out. Also I don't know if it would be related but my coolant temp gauge seems to drop all the way to the bottom sometimes or on one occasion I turned the car ignition on first thing in the morning and temp gauge was right up? What would be causing the rough starting? Any help appreciated, cheers Edited October 2, 2014 by chunkymunky1988

[paul.h]

First guess for all the problems would be a faulty coolant temp sensor and these are around £20. If you have a code reader that gives live data you can see what temperature it is giving and decide if it is wrong since before starting a cold engine it will be about 15°C and go up to about 95°C once the engine is hot.

[chunkymunky1988]

Any idea where the sensor is located and if it is easy to change? Cheers

[paul.h]

The parts diagram shows it is in the side of the thermostat/hose connector housing on the gearbox end of the cylinder head and has a green plug on it. It is held by a clip and has what looks like an o-ring seal and has Citroen part no. 1338C1, clip 1338C3 and o-ring 1338G5. You are best to get the parts from a dealer using your car VIN to make sure you get the right bits.

 

To replace the sensor, the coolant expansion cap should be removed to release any pressure, the electrical connector removed, the clip removed and then the sensor pulled out and the new one with its o-ring quickly put back. If you are quick and maybe use a thumb to plug the hole, it may be possible to do this with only a slight loss of coolant and without having to drain the coolant first (although I have never tried this). Some tissues/rags under the sensor area will minimise spillage over the gearbox. The coolant level may need topping up and on top of the thermostat housing a bleed cap is shown which should be used to let out any air. A new cap may be worth fitting but it is not the same as a tyre valve cap and its part no. is 540402.