Originally Posted by billha
I've never liked how hot both of my Bonnies run. And according to others, what mine do is "normal". You'd think GM would have set the fan trip temps lower in order to cool the engine better. I remember reading the temp trip values in the shop manual, but I don't remember what they are offhand.
Once I drove my '92 to the mountains on a day when the outside temp was around 70 degrees F, and within 10 minutes or so the temp gage was about 1/8" from the red, so I pulled over and opened the hood, expecting to find leaking coolant, but everything was dry and the coolant level was still full, so I continued the trip with the AC on, and the temp went down to around 200 quickly and stayed there. I told a GM mechanic about this trip, and he said it'* "normal" for these engines to run that hot and there'* nothing to worry about, not even at 240 degrees. I've never owned a vehicle that got so close to the red while operating under "normal" conditions!
I'm soon planning to install 180 tstats on both of mine, but I wouldn't be surprised if they both still run at 220 or higher during extended idling ("normal" here in So. Ca.) or on warm 80 or 90 degree days...that'* what both of mine do now, and I assume they both have stock 195 tstats in them.
The episode that really scared me was on a mountain pass. Driving in the snow, about 20° ambient temps, my car overheated. Not a steep grade, either. Did the same thing on the way back. The whole trip was with the 180 installed. I realized on the way back that it was slush blocking some of the openings on the front of the car, including the air gap between the grille and bumber. Cleared out the slush, and it cooled right down. Restricted frontal airflow is a killer on these things, too. With my drilled 180, I don't have this problem any more, and my smaller diameter driving lights may also allow a bit more flow.
I never see the scary temps over 200 any more. We'll see how it reacts in summer weather.