Join Date: Jan 2009
Location: North Ridgeville, Ohio
I feel really stupid for asking this, but it's one of those "second opinion" things.
Okay, background information. I bought the Cougar about 13 months ago; when I was driving it in the warmer summer weather, the temperature gauge typically remained either over the "N" or with the needle just touching it from the left. As the weather cooled off, the needle naturally settled a little lower on the gauge, about 3/4 from the inside of the white bracket past the blue zone to the "N". It's hard for me to remember for certain, but I seem to recall the needle typically hovering anywhere from 1/2-way to "N" (from the inside of the white bracket after the blue zone) to 3/4 to "N".
Now this is where trouble started. Driving home one night while on the freeways, the temperature gauge barely made it past the blue zone. The heater wasn't getting very warm; barely warm enough to keep the car at a comfortable temperature driving down the freeway in low teens. The needle was fluctuating a little, moving about a needle thicknesses up or down.
I got the car home and replaced the thermostat with a Stant 195 (economy) unit from AutoZone, and to be safe I also replaced the gauge sender. I tested the thermostat by running the engine at about 2000 RPM until the fan kicked on, which happened by the time the needle was between "N" and "O". The gauge seemed to run in the "cold weather" range I described above (1/2-3/4 up to N past blue), for a while. Then it started to only get about 1/4 up to the N. Again, I assumed the thermostat had croaked. So I went to NAPA this time and got their replacement thermostat and took out this "new" thermostat.
I put both into a pot of hot water and watched as the temperature increased, the "old" Stant opened noticeably faster than the new NAPA thermostat. So the NAPA thermostat went in for the remainder of the winter, until I started driving the T-bird again. However, the gauge started only making it up the gauge about 1/4-way to N again, so I now assume that thermostat has died.
I have a new "premium" Stant here ready to go in. I'm assuming all these thermostats have somehow just gone bad as a stroke of poor luck. Is there something I might be missing that is killing thermostats?
I wish I had a way to get actual temperature readings while on the road. I might pick up a cheap probe thermometer if this keeps up to see what's going on.
97 Laser Red Thunderbird LX 162k,
Stage 2 4.6L 2v N/A | 300 BHP (255 RWHP, 290 RWTQ) | 13.95 @ 97.58
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