'00 XLT 4X4 5.4 92,000

When I crank the truck first thing in the morning, the oil pressure gauge isn't operating (pegged on "L") and the oil pressure / coolant temp / oil temp warning light is illuminated. After a few minutes, the light goes out and the gauge starts working and shows a normal level. The oil level is fine.

Any idea what this is about?

Thanks for the help.

 

What weight oil are you using, and what is the temperature outside? If you are using a heavy weight oil and it's too cold outside, the viscosity may be too high for the oil pump to pump it quickly. When the engine is still cold you might be getting very little or no oil circulation. Once the engine warms up a little the oil pump may be able to handle it better and pumps the oil normally, resulting in the light going out and the pressure gauge showing normal.

Question: when you start it up in the morning and it shows no pressure is there any extra noise from the engine that goes away when the pressure comes up?

 

I just bought the truck, so I don't know about the oil weight. I'll be changing it soon. It has been cold here (Atlanta) but I bought the truck in Kentucky which is, of course, colder than it is here. Nevertheless, your explanation makes sense. There is no noise of any sort while the light is on, and no noticeable change after it goes out. Strange.

 

One of the first things you would notice if there was a lack of oil would be the lifters making a lot of noise, but since yours is an OHV engine it might not make that much noise. It looks like your having lows in the upper 30s? I wouldn't expect that to be a problem unless you had something like 20W-50 in there.

does yours by any chance have a block heater? If so, try plugging it in for a night and seeing if it still does the same thing in the morning. If it still does it, then it's probably not the oil. I would start looking for a bad oil pressure sending unit or gauge. If it shows oil pressure right away then I'd change your oil as soon as possible (or keep pluging it in).

 

Do yourself a favor: Spring for an oil change with a good synthetic like Mobil 1 and note any change in oil guage/light behavior. The P.O. may have put a very heavy oil in the sump to disguise some type of operational issue.

 

I have the same problem with very cold days (below 30) and I run 0w20 Mobil 1... It isn't an actual problem with pressure on mine as I have tested it and shown Oil actully movig... There is a shuddering noise after a start-up... it's almost like a set of gears doesn't mesh properly until they are a certain temp...

Once at operating temp... it pops right up....

 

I paid close attention this afternoon when I left for the first time. The oil pressure gauge is 'activated' when I crank the truck. The needle lifts up just a bit to 'L'. The oil pressure warning light stays on. I watched the temperature guage also, which, of couse, started off at 'C'. After about two minutes, as the temp gauge was slowly coming off 'C', the oil pressure warning light abruptly went off and the oil pressure guage popped up to a normal level.

In other words, the oil pressure guage doesn't slowly increase from 'Low' to a normal level as the truck warms up (as the coolant temp gauge does). Rather, it's like someone flipped the switch and it just immediately starts reading correctly.

Any ideas?

 

Apparently, at some time in the past, Ford grew tired of owners running to mama (the dealer) everytime the oil pressure guage needle fluctuated. Their cure? Dumb down the guage. Instead of providing real-time oil pressure readings, the guage needle moves from low to medium to high, with no gradations in between. Been that way since at least the intro of the Expedition, if not earlier.

This all of course begs the question: Is the protracted low reading you're witnessing accurate, or a function of some defect in the guage, sender or wiring?

 

Hmmm... that sucks. Is the dumbing down a function of the gauge or the sending unit? I mean, could you just go get a regular sending unit and use that and get real time readings? Or is there any way to get real readings on it?

 

Hi, I have a 2001 4.6 I bought used in May with 60,000 miles. Just started having the oil pressure guage go to low after it's started. If I turn off the engine and restart it's been ok. This is even after having the oil changed by the dealer.

Also have seen the guage read ok, drop down to low with oil light on, then in a few seconds jump right back to normal and back to low.

I am hoping it's the sender or a wire - understand the sender is near the oil filter housing. Any other help is appreciated.

Thanks

Mike