The Sarge

My temp guage is acting up still.


I just replaced radiator, hoses and new cummins thermostat after getting 2 brand new stants that didnt work.

What it does is wander back and forth in the middle from hot to cold between the two middle needles if you know what i mean.

I did a search and sounded like its pretty normal could it be a temperature or thermostat guage sensor problem or should i not worry about it??

Thanks.

jimbo486

did you install the thermostat with the "jingle pins" in the 12 and 6 o'clock positions? maybe a bad sensor in the head?

The Sarge

Yeah thats a 10-4. Is that the right one??

jimbo486

the cummins thermostat is the one that seems to offer the best results if installed correctly ("jingle pins" at 12 and 6 o'clock). as i understand it, you did, correct? mine doesn't float between the 2nd and 3rd marks on the gauge anymore since i replaced it back in august with a cummins thermostat. i'm also using my original sensor. if everything else is in check, my guess would be the sensor.

Bob Beauchaine

My Dodge temp guage has wandered between the first and second pins for at least 5 years. While the dodge guage wanders my after market temp guage may moves about 2 to 4 degrees. With my fan on it barely moves at all, I only turn the fan on when the A/C is on and I am in traffic. The movement does not concern me as the truck does not overheat.

Bob

The Sarge

Alright thanks fellas i think i might replace the sensor and see what it does........it doesnt overheat though so i think its ok.

Thanks.

rustydeeretech

from what i understood was that the radiator is so big the the engine cant heat up the whole cooling system in cold weather just driving around with no load so the t stat is always opening and closing because mine will do the same thing until i start pulling hard on it on a hot day

Jim Lane

A loose ground at your instrument cluster can also cause all or some of your gauges to wander.
Does your fuel gauge also wander?
Mine did until I grounded my insturment cluster circuit board.

Jim

rustydeeretech

no its only temp and i know i have a good ground also if i just let the truck idle of im easy on it not working it it will slowly move compared to when im on it

M1Lover

Sarge, its entirely likely that the gauge is accurate and reading the temp correctly as your thermo opens and closes, opens and closes. I put a new Cummins T-stat in, just like you're s'posed to and the temp needle was rock solid. Then I did it again to make sure it was my head gasket leaking and not the thermo housing (It WAS the head gasket). I did the same thing as you. New upper and lower hoses and clamps. New T-stat gasket, put the Cummins T-stat back in, cuz it worked fine. Now my temp gauge is acting like yours. Has for a while now. As the truck warms thoroughly on longer trips the gap between the extreme swings lessens, little by little. That doesn't make you feel good though when you glance down and see the needle on the high end of the pendulum and think Holy Cow, I'm overheating! Oh, yeah. Wait a second. there it goes, letting that cool radiator coolant in and cooling it all off again... Seems this is common. I've put a nipple and plug on top of the T-stat housing to try to get any air out. None comes out. Needle still swings. I'm tired of looking at it and worrying about it, so I ignore it now..... YMMV. Good luck. H.

jimbo486

mine doesn't swing at all. i can watch mine warm up to about the middle of the gauge, then the thermostat opens and it falls to the 2nd line and stays there. it might warm up a bit after a while but it barely moves past the 2nd line and then the thermostat opens again and back to the 2nd line it goes.

The Sarge

Hey M1 Lover,

Thanks for your telling me your own experience. Sometimes you think you are the only one with the weird problems these trucks can tend to have .

As far as my head gasket i am pretty sure its not that.....I could be wrong but there are no obvious signs i see.

Jim Lane,

I will check the ground soon as it warms up around here pretty cold with the wind for a open driveway work.

Thanks for all the replies i appreciate it helps trouble shooting become so much easier. Thank you.

Kyle

RSWORDS

That or the ground from teh battery to teh core support... That one is VERY under sized and causes all sorts of odd electrical issues.

raggmann

I've got kind of a similar issue-my needle bounces all over the place then last night it just went to the cold side and stayed there.
Sensor?
Gauge?
How does one tell?