DannoP

ok so heres the deal. When i got the truck from my brother the temp guage was kinda of weird and moved around alot. It would go to the hot end of the normal bracket then back down to around the middle. I noticed the other day that it now goes up and seems to stay. The faster i drive (usually no more than 55) the higher it gets. It never gets outside of the Normal bracket but its close. When i stop at a light it drops back to alittle above the middle.


Any ideas on what this could be. I have not replace anything as of yet and will try to pull codes this weekend (never done it so that should be fun) and check Antifreeze.

BigGreyBox

Being low on coolant usually makes for screwy readings on the gauge. The fact that you said the gauge drops when you come to a stop, and increases when moving is complete opposite of normal obviously haha. It could also be a sticky thermostat, bad coolant temperature sensor, or coolant temp sender.

ymeski56

Everything but the ECT senor could affect the guage reading. Burp the system to start w/. If you've Have been running excessive temps, that in itself will tweek the thermostat, requiring it's replacement. When you fill a radiator, fill it cold, start the engine w/ the cap off. Continue topping it off till the engine reaches norm.op.temp. ,replace cap and fill overflow tank to warm line. Air is many times trapped in the heater core loop, so make sure it's temp setting it on high (fully open). Be careful, or you'll end up looking like that guy that's always wearing the hockey mask!

BigGreyBox

yea when my temp sensor went bad I lost a lot of power and got mileage like death, so if it seems to still be running fine I guess that wouldn't make sense.

J.A.C

also check for any leaks in system that would make it lose pressure and some times it moves like that.

ymeski56

You still get an 80%. I omitted the possibility of a possible leak, so I was only 90%. I guess sometimes, it does take a village (forum) to fix these d*mn trucks!

BigGreyBox

haha I can live with an 80, its still above average! You guys ever listen to Car Talk on npr? This forum is like a never ending source of puzzlers.

DannoP

Thanks for the info. As far as i can tell there are no leaks. Ill check the water/coolant level this afternoon after work. will be getting a new thermostat also to put in this weekend, cheap and cant hurt right.

flareside_thunder

There's two different coolant sensors on these trucks...one with the coolant temp sender and the other is the engine coolant temperature sensor.......the latter is what makes the truck run like sh*t. The first is what sends a reading to the gauge on your dash.

ymeski56

flaresidethunder........ Your killin me! A SENDER is not a SENSOR. ECT Sensor. Collant temp. Sender! Other than that, your 100% correct. And yes, I love those guys on NPR too! (calling them both "sensors" results in many readers replacing the wrong one)