Good evening, I'm noticing a issue with my wifes truck upon start up. First off it's a 2000 Dodge Dakota 4.7 V8 with around 110k on it.

Now let me tell you that it has been cold here with a lot of snow the last few weeks so I don't know if that's the problem or not. But anyway, upon start up it's taking about 5-8 seconds for the oil pressure to come up to normal, about 40 psi. The "check gauges" light is illuminated during start up. Soon as the pressure reaches normal operating psi, the light turns off. My wife has also stated to me that when she is disengageing the 4 wheel drive the "check gauges" light comes on and off. She hasn't noticed the oil pressure during this evolution, but I don't know if that has anything to do with it.

I'm wondering if the oil pump is starting to fail or it's a faulty gauge issue. Or maybe something else. If you have any suggestions on where to start investigating I'm all ears. BTW, it does have adaquate oil in the pan. Thanks in advance.

 

How cold is cold?

How old is the oil? And what brand/viscosity?

 

By cold, do you mean 25 degrees or -10 degrees? What weight oil are you using? If you're running 10W-40 for instance, it's just stiff lubricant.

On the "check gauges" light, how about the check engine light? The first thing I'd do there is check the computer for codes. AutoZone will do this for free since if you need a part, you'll probably buy one from them while you're there. Even if the CEL isn't lit, you may have some codes stored in the computer. All gas from 1996 and most diesel engines from 1997 and up run OBD II. You can buy a cheap reader for less than $100. I'll bet one of the mechanics at the motor pool has one handy at the coast guard base.

Now, all your lights on the instrument cluster will light up when you start it to show they're working. Cars have done this since the early 1960's. Otherwise, you'll never know when a bulb burns out.

 

Oil has about 10k on it, 10w-30 Quaker State. At night it get any where from 10-25 degrees.

 

Quaker State is a pretty good oil. It's probably got enough of a film so that there's no problem inside the engine. If it's in the teens and takes a few seconds, I wouldn't worry about it. Just don't race the engine until it's warmed up. Let the pressure stabilize before driving and you should be good to go. If there aren't any codes in your computer, I don't think there's anything wrong with your truck. At least your wife is paying attention. That will make your truck last longer.

 

No codes, engine light hasn't come on. I know this truck has 137 codes stored for the check engine light, but this is not the case Maybe when this snow storm breaks I'll take it to Auto Zone. Only problem is it's in Reno or Carson City. About an hour from me, plus this large snow storm hitting the west coast right now.

This is different from the self check upon start up, all lights are working. The "check gauges" light stays illuminated longer than normal with no oil pressure. I've owned this truck for 10 years now, bought it brand new.

 

The sensor could be taking longer to close and make a ground.

 

Jeep oil pressure sending units are notorious for operating incorrectly. Probably uses same or similar.