93 Accord EX - temperature gage periodically stays at bottom (cold) with minimal heat produced by heater even at full setting and over long distance trips. Other times, gage shows normal operating temperature and heater once again functions normally. I was wondering what the most likely cause was: malfunctioning thermostat, faulty sensor or engine temp. gage, rotten heater core?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by charlie53 &raquo;</TD></TR><TR><TD CLASS="quote"> I was wondering what the most likely cause was: </TD></TR></TABLE>
T-stat or low coolant level.

 

if your coolant level is where it should be then check the following

1. T-Stat stuck open or intermittent failure

2. water pump for proper operation


I would replace the t-stat and flush the system.

 

My guess in T-stat is stuck open and engine never warms up fully (sounds weird but they do rarely get stuck while open). FYI that hurts your gas mileage and it'll warm up faster (if at all) if you don't turn on your heater. You might try letting it idle for a while and seeing what happens, if you drive around too early it'll cool off due to air flowing through the radiator.

On cold startup your coolant cycles through the engine only, after it warms up only then does the t-stat flip open and coolant is cooled off through the radiator. If t-stat starts open it'll continue to cycle already cool coolant and will never warm up.

 

my t-stat was stuck in the open position and it affected the following

1. fuel milage
2. Torque converter lockup would not happen.