My problem is with a 93 Geo Prizm, 80K miles. I was out for about an hour
yesterday and noticed the dashboard temperature gauge stayed at cold the
entire time. After some searching I get the impression I need a new
thermostat. Is that the likely cause? Is it safe to continue driving like
this?
If it's the thermostat, is this difficult to change? (Not too experienced,
most ambitious project was an alternator change.) I'm going to track down
a Chilton's guide today.
Also, I've read this requires a coolant change. If that's the case, what
should I use to replace it? I'm in the DC area.
Any help is appreciated. Thank you.
MG
> My problem is with a 93 Geo Prizm, 80K miles. I was out for about an hour
> yesterday and noticed the dashboard temperature gauge stayed at cold the
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>
> MG
It sounds like the thermostat is stuck open, which all it is doing is
allowing the coolant to constantly flow thru it without regulation. How is
your heat?? Or should I say do yo uhave any heat?? Prob not....
Changing the thermostat isn't a problem at all.. all you need is the
right sized wrench, a new thermostat, a gasket, and a razor blade....
Carefully remove the two bolts around the thermostat housing... I say
carefully because they have a tendency to be hard to remove... sometimes
snapping...once you get the bolts off, pop out the old thermostat (with a
screwdriver if needed to pry upward),and remove gasket with a razor blade,
making sure the surface is nice and smooth. You may not need a razor blade,
but inspect it to make sure surface is smooth.... Pop new thermostat in
place with gasket, put housing back on with two bolts.... tighten to
specified torque, or if you don't know what that is, just tighten til you
think its tight enough (won't leak)...
good Luck
Fwed
MG - 08 Jan 2006 20:02 GMT
> How is your heat?? Or should I say do yo uhave any heat?? Prob
> not....
Thanks for the response. Actually the heat seems normal. Does that still
mean a bad thermostat?
MG
fweddybear - 08 Jan 2006 21:01 GMT
>> How is your heat?? Or should I say do yo uhave any heat?? Prob
>> not....
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>
> MG
Might not be then.... I mean if it still gets hot in the car... it could
be your gauge, or where your gauge connect to the thermostat housing....or
wherever it conects....you can check your gauge to see if it is getting
power with an ohm meter. If not, then check it back at the connector to see
if its getting there... in fact, its a little harder to check the gauge than
to check the terminal... so maybe do that first...
Fwed
MG - 08 Jan 2006 23:04 GMT
> Might not be then.... I mean if it still gets hot in the car... it
> could
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>
> Fwed
I'll check it out. Yesterday it was at the 'C' line the entire time.
Today it started out at C, then climbed to about 1/5th of the way up, then
went back down to C once I got on the highway. Strange, it's not
completely dead.
Bob M. - 11 Jan 2006 06:30 GMT
>> Might not be then.... I mean if it still gets hot in the car... it
>> could
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> went back down to C once I got on the highway. Strange, it's not
> completely dead.
The car won't go "dead" with a cooling problem, not when it's running too
cold anyhow.
Is the cooling fan on the radiator running all the time when the engine is
running? Turn off the a/c and the fan should run only when needed.
But, I think you are looking at a new t-stat. Also, have you checked the
coolant level in the overflow bottle? You say it's time for a coolant
change so this would be taken care of then. Best coolant mix is 50%
distilled water and 50% coolant.
I had a '93 Prizm with the smaller engine but I can't remember the location
of things anymore, having sold it in '98.
MG - 11 Jan 2006 23:52 GMT
> The car won't go "dead" with a cooling problem, not when it's running too
> cold anyhow.
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> I had a '93 Prizm with the smaller engine but I can't remember the location
> of things anymore, having sold it in '98.
Thanks for the response. The overflow bottle is at full and the cooling
fan is not running all the time. The temp gauge has been intermittent
over the past few days.
I was about to try fweddybear's tests when I noticed the fuel gauge and
speedometer are acting up too. The fuel gauge stays at 3/4 full, even
when the car is off. The speedometer is sluggish. It'll keep rising
when I brake and hang at 10mph for a few seconds when I'm stopped.
A few searches suggest the instrument voltage regulator. Does that
sound about right? Is this separate from the alternator's? If so, is
it a difficult repair?
Bob M. - 14 Jan 2006 02:44 GMT
> Thanks for the response. The overflow bottle is at full and the cooling
> fan is not running all the time. The temp gauge has been intermittent
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> speedometer are acting up too. The fuel gauge stays at 3/4 full, even
> when the car is off.
That may be normal. Some cars do that.
> The speedometer is sluggish. It'll keep rising when I brake and hang at
> 10mph for a few seconds when I'm stopped.
>
> A few searches suggest the instrument voltage regulator. Does that sound
> about right? Is this separate from the alternator's? If so, is it a
> difficult repair?
I have no idea.
fweddybear - 14 Jan 2006 03:22 GMT
>> Thanks for the response. The overflow bottle is at full and the cooling
>> fan is not running all the time. The temp gauge has been intermittent
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>
> I have no idea.
You may have a common ground that is not making its best connection. I
remember a time when my whole instrument panel, gauges and all, were dimly
lit and not functioning all that great... it turned out to be the ground
wire from the fuse block to the neg terminal of the battery. It was hanging
on by a few threads....the rest of them were corroded......I ended up
installing a new cable and all has been well since. that was two years
ago....
Fwed