Contour Enthusiasts Group Archives Forums General Troubleshooting very low temp gauge reading

My temp gauge used to read pretty much in the middle. A while ago it started reading from below the N to the line at the bottom of the range. It also was not stable anymore sometimes it would be at the N other times all the way down at the minimum line and it would bounce around too.

Mechanic replaced thermostat he said the gauge was reading correctly and temp was a little low. Initially was acting more normally would rise to between N and O and stay there.

But about a week later noticed it is acting strange again. One day after driving about 6 mi I noticed the needle pointing at that line to the left of the N again. I stopped at a light and after a bit the needle rose back to between the N and O and stayed their for the remaining few miles to home. Then today it had warmed up to between N and O then it dropped back down to halfway between the N and that min. line.

The temp used to be stable, what would cause it to start bouncing around like this besides the thermostat that was already replaced?

Might be a flaky temp guage or sender is causing flakey readings.

The guage and sender might be reading correctly but your temp is fluctating.

Have to determine which, first.

Best to install a known good temp sensing system so that you know.

Assuming the indication you are receiving is correct, your problems may be the engine cooling temp sensor, the PCM, the radiator fan and it's associated control relay, the radiator, the water pump, or maybe even something else obstructing the coolant flow through the system. Might be ir pockets in the system, although they usually disipate over a few driving cycles.


Try to observe if there is any correlation between the cooling fan operating and the swings in the temp guage. Also, note that the AC, when turned on, should also turn on the cooling fan.

Have fun...

Steve

I think I'd check the connector and terminal at the sender before doing anything else.

Getting back to this...

Mechanic said actual temperature reading showed it was operating as it should with the new thermostat. I thought variations in temp readings according the the gauge in the dash were unusual, he did not think so...he just thought maybe I was watching the gauge more. It did seem to me that temp reading used to go up and then be pretty stable, but maybe he is right...

Oh and he also said part of the problem may be the gauge in the car, said it seemed to respond very slowly. He did tell me that the middle of normal was 218 on my car and the N was 188...kind of nice to know that. So I am guessing in my case the L might be around 238, then.

He said he put in a 195 deg thermostat in...is that unusually low? I thought cars were supposed to run hotter than that these days. I used to have a vehicle with actual temp gauge and it used to run at about 215 I think.

One last thing...Is a "normal" reading on the gauge in our cars supposed to be when the needle points at the word "normal" or does a normal reading include everything between the two lines. I always thought it was everything between the two lines, but mechanic says only the word. Of course, if I ever got up to the "L" I think I'd be doing something about it anyway...but just curious. Well, maybe I should have checked the manual first ...but I did not think of that until after I typed this paragraph.

On my 'tour, I normally sit between the N and R. If it goes above the R I'm usually in stop-and-go traffic, or sitting at a stop immediately after having been on the highway for a while. The fans kick in and the temp returns to normal. I know my car enough now to know when she's getting too warm.

I've heard about a lot of variation in temp. guages on these boards. There was a Mystique that routinely sat at the m for years with no overheating problems. You may just have to get used to how your temp guage reads.

If you're ever unsure of your actual temp, you're more than welcome to drive down to Oak Creek, and I'll scan your car. Ditto for CELs.

According to the Ford Service Manual for a 95 Contour Zetec, the thermostat starts to open at 187-194 F, and is fully open at 216 F.

Okay, I believe he said fully open at 195 so it is a bit colder than original thermostat.

Probably won't take you up on that, but thanks for the offer .

I know those electrical gauges are not the most accurate or consistent. Mine now runs in that same range, which is about 188-218 on mine according to mechanic...used to run a little hotter with original thermostat.

This one used to sit right about the middle...which makes sense given the original thermostat specs and the info from mechanic.