What would cause the running engine temperature of my diesel pickup truck to fluctuate randomly?
I have everything on my truck monitored (egt’s, engine temp, trans temp, ect) and they all act in their usual manner but just a couple days ago I noticed that randomly during my drive to work my engine temp would jump up 70+ degrees. I checked my coolant level and it seemed good and my truck didn’t perform differently so I wasn’t too concerned about it but it is out of the ordinary so I thought I’d see if anyone had any ideas as to what could be causing this and what I may have overlooked. Thanks!
I have everything on my truck monitored (egt’s, engine temp, trans temp, ect) and they all act in their usual manner but just a couple days ago I noticed that randomly during my drive to work my engine temp would jump up 70+ degrees. I checked my coolant level and it seemed good and my truck didn’t perform differently so I wasn’t too concerned about it but it is out of the ordinary so I thought I’d see if anyone had any ideas as to what could be causing this and what I may have overlooked. Thanks!
Sorry I didn’t include the make and model. It’s a 2003 Ford F-350 with the 6.0L powerstroke.
A flaky thermostat
That sounds more like a sensor malfunction than the vehicle actually having any mechanical problems.
But, I guess the next question would be, when you shut the truck off and start it back up, does the guage read the usual temperature, or the 70+?
Your cooling system seems to have air in it. Air can get much hotter than the liquid and send your sending unit to it’s max. Make sure you have removed All air from the system.
70+ degrees is optimum fuel temperature in must Diesel engines.
if You talking coolant ,then ,.check thermostat.
P.S. next time give us the make, model, year.please!
if you hauling tractor trailer(18 wheeler),what was Your load that day.
it could be an air lock or sensor malfunction or the wires ,is the gauge grounded correctly ? perhaps even the gauge itself is going bad , checking these things will eliminate most of the probable causes
If the guages are electric then the (sender works off of ohms resistance and sends the reading to the guage) the wire from the sender to guage is possibly grounded some where. This gives you a resistance reading to the guage. The guage will respond to the resistance and the needle will be fluctuate.