Vauxhall Vectra C - Engine Water Temperature - wellman

We have an ongoing problem with my wifes Vetra C bought new in 2003 and now covered 54000 miles 1.8 XE model.

The vehicle is mainly used for short runs approx 7-10 miles. The engine water temperature gauge does not appear to reach what I believe is normal operating temperature, according to Haynes manual the thermostat opens at 92c. On trips of 7 miles with an outside air temp of 1c the gauge does not move of stop and on longer trips of 10-12 miles does not go above the 1st marker line (60c ?) and only then towards the end of the trip. However when stationary the temp will go above 80c but when movng again will drop back to zero.

The thermostat has been replaced twice and the sensor is part of the stat so it carn't be that. The heater works OK and hot air enters the car within a few minutes of driving off. Is this low temperature likely to cause damage to the engine.

Does anyone have any ideas as to what the problem is.

Many thanks Wellman.

Vauxhall Vectra C - Engine Water Temperature - unthrottled

The first step is to find out if the temperature gauge is actually reflecting the coolant temperature. The fact that the temperature gauge is dependant on road speed would suggest that the thermostat isn't sealing very well in its housing. Even a tiny gap will keep the engine running cool when it is cold outside.

If you run the engine for a few minutes, the water temperature in the engine should be noticeably above ambient, whilst the hose from the thermostat housing to the radiator should be absolutely stone cold-right up to the T-stat. If it is getting warm prematurely, you need to look at the fitting of the thermostat more closely.

If the engine is genuinely running cool, you'll get poorer fuel economy and more contamination of the oil with fuel.

Vauxhall Vectra C - Engine Water Temperature - Collos25

Check to see if the engine cooling fan is running all the time.

 

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