Slow warmup - 2000 Dodge Caravan

Looking for some advice...

We have a 2000 Dodge Caravan with a 3.0 litre engine. The van runs well but
we have one small problem...

When the weather is cold, a few degrees above freezing or less, the engine
can take a long time to warm up when being driven. I've been able to drive
highway speeds for 15+ minutes and the temp gauge still does not come up to
normal.

If I start the van and let it idle, it comes up to normal temperature much
quicker.

Am I correct that this is just a faulty thermostat, or should I also be
looking elsewhere?

Thanks!

 

Sure sounds like t-stat stuck open.

 

And make sure you top up the cooland in the RADIATOR, too, else it
may never get hot liquid into the heater core.

Thermostats fail. often. I got maybe 2-3 years out of any in my
Caravan(s). /mark

 

And before you put the new one in, test it in a pan of water on the
stove with an accurate thermometer - I have read of getting bad
thermostats right out of the box - happens more often than you'd think.
Ounce of prevention...

 

And furthermore, make sure you don't cross-thread the bolts when
you put them back in. The one time I took it to a shop instead
of doing it myself..... Well, you can guess what happened....
sigh...
/mark

 

Thanks for all the advice folks!

One more question... would it be worth while to do a coolant system flush
too?