Engine Underheating ?

[BRICH1260]

Hey guys, new member here with a question. Just purchased a `02 Chaparral 243 Sunesta. It has the 5.0 gxi-b engine. Have had it out three times now. The temp gauge never reaches " normal operating range". The gauge is reading somewhere in the 140 degree range and never fluxuates. The engine seems to run fine, no misses. Is my thermostat stuck open? or perhaps a faulty gauge? Whats the best way to diagnose without tearing into the engine. Thanks for your help.

 

[Don S]

Re: Engine Underheating ?

Get one of those IR temp guns and check the temperature right at the temp sending unit on the engine and see if it says the same thing as your temp gauge on the dash.
Yes, it could be a thermostat and it could also be a gauge or sender problem, or even a corroded terminal somewhere.