oil pressure drops

[tangle06]

i hope someone can help me with this...i have a 2000 ranger 3.0 v6 that has had its motor replaced...this is the problem: after about an hour of drive time, the oil pressure gauge will start to flicker...at the same time, the temp gauge will start to rise...then the engine will die out...help!

 

[GMWIGGS]

Not sure if you have an electric problem or what. The motor heats up, oil pressure drops down to the point the guage is flickering (about 7psi I believe) and the temp guage starts to rise. Sounds like it can't hold enough oil pressure at operating temp to properly lube the engine? Is this at highway speeds or at an Idle? Auto or Manual tranny?

 

[Earl43P]

A lot of information is missing, but I'll take a shot at this too.


If you are driving at highway speeeds THEN come to a stop and the idle is lopey and the oil pressure gage flickers: You have a low idle problem. It MAY be an EGR problem (valve stuck partially open makes it idle poorly). It may also be a bad DPFE. It could be as simple as a bad plug wire or spark plug. It is not unusual for the temp gage to rise after a stop from hiway speed. If you goose the gas several times while waiting for the green light, it should come down.

If this is happening while you are driving at speed, then I have no idea.

 

[tangle06]

thanks for your responses...here is a little more info: from initial start-up and idling, the truck is fine...it can run for hours with no problem...but when its on the road it happens...a few times the motor has died while the truck is on the move...i have to pull to the side and restart, which in some cases the truck dies after a few seconds...i have to rev the motor and then it'll be okay...btw, the truck is an automatic.

 

[locknar]

on many vehicles the oil pressure sending unit will cut off the fuel on a low reading ( sorry not sure if you have that). If you did that would account for the motor dying. Revving the engine brings up the oil pressure.

As these senders are prone to failure, and are only a $27 item I would replace the sender, if you get lucky that could also fix the stalling.

If not the question is why the low oil pressure? As the oil heats it looses viscosity and becomes thinner, so a hot engine will have lower pressure readings than a cold one. You could change to a thicker oil. Other than that the rest of the possibilities are expensive.