Hi all,

I recently posted a thread about my oil guage not working properly. Well, today I was driving and my temp guage shot up to over temp. I turned the heat on full blast and while idling the temp guage is full blast hot and but the air is very cool like air conditioning would feel. when I rev the engine up to a high rpm the temp guage goes back to normal level, but the air gets very hot, to the touch. I changed the water pump and thermostat about 1.5 yrs ago and havent had a problem until today. the oil guage is also acting very weird. Does anybody have any input? Thanks in advance.

 

what engine and year? but i would guess its a bad tstat.

 

4.7L V8. 2003. Yea I was thinking the tstat was sticking, but it is only 1.5 yrs old.. guess it could still be bad though.

 

It could possibly be a bad thermostat. It could also be the heater core is partially plugged, and the coolant does not circulate through it at idle and it causes the overheating and lack of heat output from the vents. The truck can have heat from the vents and the temp gauge can come back down when you rev the engine or drive the truck because at that RPM there is enough pressure in the heater core to force some coolant through and circulate it in the cooling system.

Before replacing the thermostat maybe try to remove the heater hoses and back-flush the heater core. I don't know exactly how to do it on a 4.7 but it's probably on here and you can find more info on it using the search function. It's probably about the same process as my 3.9, disconnect the heater hoses at the water pump and thermostat housing, direct one hose into a 5 gallon bucket and use a water hose in the end of the other heater hose to flush all the gunk out. Flush for a few minutes, then reverse the hoses and flush in the opposite direction. Do not use too much water pressure though, so you don't force any gunk back into the engine block. Then top off your coolant and see how it does after that.

I do know plugged heater cores are kind of a common problem on Dakota's. Let us know how it turns out.

Jimmy

 

Thanks! I will try that as soon as I have time. I am in the process of moving, so it will probably be a week or two, but I am going to try flushing first. Thanks for the input.

 

Have you checked the level of the coolant? What's going on with the oil gauge?

Blown head gasket?

 

This is the issue with the oil guage that I just started seeing less than a week ago.

There are just about 70k miles on the engine, and I just recently started having an issue. I changed the oil and filter about 450 miles ago just before taking a road trip from Colorado to New Mexico. Ever since I have been in New Mexico I have noticed that when starting the truck the oil guage is very slow to come up to normal place and from the time I start the truck to the time the oil guage gets to where it should be the truck shakes, it seems to me like it could be the oil pump, or the filter I put in is possibly clogged. Please give me so info on what to check as there may be something even easier that I do not know about.

I added a quart of oil the other day and has helped a little, but still seeing the issue. Before I added the quart the level was right at the good line, when I added the oil it went above the line.

Thanks