High running Temperature

For years my trusty Vectra B 1997 has been running fine, temp gauge usually
just over 80 on the motorway. However recently it moved higher towards 90.
In traffic its hit 95. If i leave it running static i can get it to just
under 100. The radiator fan runs fine, 1 kicks in at just over 90, the 2nd
at 95. Coolant is ok. Car seems to run fine, just hotter than usual.

All I have done is added some STP engine cleaner to try and cure knocking
from the injector area at low revs and idle.

Any suggestions??

Don't think its the thermostat as the fans wouldn't kick in at high coolant
temp.

 

What engine is it?

Does sound like the thermostat to me. Coolant temperature thermostat is a
different component to the fan control thermostat.

Mike

 

Its a XEL16, not sure exactly. a 1.6 16V Arctic from 1997. Runs perfectly
other than knocking at low revs and high running temp on the motorway.

 

Water pump impeller blades rusting out, time for a new water pump??

You are using anti-freeze I expect. Plain water can run hotter...

Brian W

 

Yes I am using anti freeze. Its a dark green colour, and if tasted you cans
taste the glycol in it (Sweet).
Not to sure about the water pump theory, thats a big job, not something I
can do at home, might as well replace the timing belt if i do that.

Is there a way to isolate if it is the pump or not?

 

I read one or two of the other contributions, and I noticed one that
mentioned the water thermostat is a separate thing from the fan
thermostats. The former is a fluid valve, the latter is an electric switch.

So if you haven't already, change the fluid thermostat first. These are
usually pretty easy to get at, and not expensive to replace. If this
doesn't work for you, you could think about changing the water pump.
You might ask a dealer to look at a replacement pump - the ones that
rust out have a cast impeller. If you have always used antifreeze, this
seems kind of unlikely.
I hope its just a thermostat.

Brian W

 

Me too. Thanks. Whilst searching on the net for similar symptoms, a few
posters mentioned having tappet noise from a sticky lifter. This caused the
engine to run hotter.

Similar symptoms i have, a knocking from the engine top at low revs,
sometimes at higher revs, but never at high(under load) revs.
I used an STP additive in my fuel to clean the fuel system in case this was
the cause of the noise (Blocked injector, dirty EGR) and the additive was
making my engine hotter, hence me asking about the hotter engine.

However the knocking may actually be the cause of higher heat in the engine.
I will look at an oil change and put in some decent fully synthetic GTX
Magnatec and see if the noise and heat issue go away.

 

I will also look at the thermostat option, if pretty cheap, will get one on
eBay and fit anyway.

 

I have changed the oil, it was dirty, despite only doing 3000 miles.

Temps back to normal.

Used AGIP Sint 2000, synthetic 10W40. It was on offer