Temperature gauge intermittently not working

2011 VAUXHALL ASTRA

35,000 MILES • 1.6L • 4 CYL • FWD • MANUAL

HENDO46

MEMBER
3 POSTS

Noticed temperature gauge not moving above zero and heater only blowing cool air even after travelling twenty miles, sometimes the gauge rises to about forty degrees and the heater blows hot but the gauge will drop to zero and the heater will blow cool again, the gauge used to run at ninety degrees.

Dec 5, 2016 at 9:51 AM

STEVE W.

✓ASE Certified Mechanic
15,200 POSTS

First thing is to check your coolant level, low coolant could cause this. Next would be to remove and replace the thermostat. If they stick open the engine won't warm up properly.
If you have access to a scan too or even a lower end tool that will read live data it can show you the temperature the coolant sensor is reading.

Dec 5, 2016 at 6:22 PM

HENDO46

MEMBER
3 POSTS

Thanks steve, coolant level is ok, will change thermostat an let you know outcome

Dec 6, 2016 at 12:56 AM

MHPAUTOS

✓ASE Certified Mechanic
31,937 POSTS

i agree, the thermostat would be the first thing that i would be checking.

Dec 7, 2016 at 4:33 AM

HENDO46

MEMBER
3 POSTS

Changed thermostat everything now working as it should, cheers guy,s and thanks for the advice

Dec 8, 2016 at 11:30 AM

STEVE W.

✓ASE Certified Mechanic
15,200 POSTS

No problem, enjoy the heat..

Dec 8, 2016 at 12:38 PM

MHPAUTOS

✓ASE Certified Mechanic
31,937 POSTS

Thanks for using 2carpros

Dec 8, 2016 at 11:46 PM

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