I've got a "cold" engine and can't seem to get it to run at normal operating temps. It constantly runs just barely over the first mark on the temp gage. If it sits at idle for a long time, the temp will rise and the fan will kick on at about 200*, since I have a JET fan switch in there. It'll then cool back down, fan shuts off. AS for heat in the car, temp has to be just about all the way over to get any real heat, move it back toward cool just a little, and it cools quick - there's almost no in between, or not much of it. Now, the set-up I'm talking about is a '91 5.7 TPI, stewart water pump, and modine aluminum radiator (from napa). recently I replaced the heater core, no real difference in heat. When I start the car, the gage doesn't peg hot all the way for "self test", but I grounded out the gage wire and the gage pegged all the way. I put a high-flow thermostat in a couple of years ago when I put in the stewart pump, but I'm just trying to figure out why it doesn't ever seem to want to reach a normal operating temp. I've been reading some of the other threads on here similar to this, but haven't come up with anything that seems to work. Last time (a long time ago) I checked the thermostat for operation and it seemed to work, but like I said, it was a long time ago... any inputs are appreciated...

 

if u have a 195* thermostat. then i would guess that ur guage is off or that ur temp sender is off, our guages aren't that accurate,, i would see about borrowing a scan tool or replacing ur temp sender..

 

what t-stat are you running?

 

Put in a stock 195 stat. What you describe sounds like you are running a 160 degree unit. Thats about where they run with a 160. If you have a 200 deg fan switch you may want a 180 stat otherwise your fans will be cycling on and off all the time.

 

I guess I forgot to add that I am running a stock 195 stat. And at one point in time have replaced the CTS and the temp sending unit. Not to say they haven't possibly gone bad, but what's making me wonder about the heat, is that there's very little heat, only when it's all the way hot or slightly cooler - there's not much leeway there at all. I guess what I'm trying to say is that I think something is causing it not to warm up. I also have a '90 IROC with the same motor, stock radiator and pump, and it warms up normally...

 

Getting warmed up is a function of the thermostat. It's stops coolant flow in the radiator until around 195 in your case. It really sounds like the stat' is stuck open or otherwise not working correctly--the only way it will warm up is at a standstill, with no air moving through the radiator. I would first replace the thermostat. What temp is the 'first notch' anyway? If you are concerned about the temp, you should run an accurate mechanical guage.

 

82 is absolutely right. If it's not warming up either the stat is bad or it's mismarked but either way just replace it and you should be ok.

 

thanks, fella's... i'll start with the 'stat...