Vauxhall Vectra C - Engine Coolant Temperature

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Thu 8 Mar 2012 20:48
Vauxhall Vectra C - Engine Coolant Temperature - wellman

2003 Vectra C 1.8 718XE engine 50500 miles

I have owned the above vehicle from new. A the beginning of October last the temperature gauge started showing a very low reading and a faulty thermostat was diagnosed which was replaced and all seemed well although the gauge did not appear to show as high a reading as before the change, Now during the last few weeks the temperature gauge hardly moves off the stop position even on quite long runs, following a run if the engine is turned off and left for say 5 minutes and then restarted the gauge shows near the 100c mark but drops back to just of the stop position when the vehicle has been driven for approx 1/4 mile, also there are times when the qauge reading fluctuates between cold and half way to the 80c mark. The Hahnes manual says the thermostat should open at 92c but at the moment the temperature is not getting anywhere near that. I assume the correct themostat has been fitted and is ok.

Does anyone have any ideas to help

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Thu 8 Mar 2012 23:00
Vauxhall Vectra C - Engine Coolant Temperature - Peter.N.

Start the engine from cold, leave it running for a minute or two then feel the top of the radiator, if its getting warm but the gauge is showing cold the thermostat is suspect again. What should happen is that the radiator should remain almost cold until the engine reaches normal temperature then the thermostat opens and the radiator gets very hot suddenly.

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Fri 9 Mar 2012 08:43
Vauxhall Vectra C - Engine Coolant Temperature - TeeCee

I have a Zafira with the X18XE engine and those symptoms are awfully familiar.

Been through two thermostats so far, they're notoriously prone to failure. QH do a repair kit containing just the 'stat, rubber-ring gasket[1] and a cardboard tube to remove / insert the thing with. GM will only sell you the entire 'stat, housing and temp sensor assembly for rather more pennies.

[1] If it's a similar housing assembly to mine, that's worse than useless. Use some instant gasket instead.

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Fri 9 Mar 2012 14:11
Vauxhall Vectra C - Engine Coolant Temperature - TeeCee

Damn, missed the edit window.

The thermostat housing is, as with much on these engines, held on with those bolts that have heads that look like the business end of a torx driver (external torx bolts). You'll need the appropriate 10mm external torx socket to get 'em off.

Don't try to turn them with a standard socket, it just slips and rounds the ridges off.

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