Check Gauge Light

[Cjpooch]

Hello All. I recently purchased a 2002 Ford Explorer XLT, it is my first explorer, and Ford. I was surprised to find a whole community dedicated to it. I like it so far, but I know nothing about vehicles and engines. My question, my check gauge light has come on a few times. It usually happens when it's colder (today it was 28F), when I start the vehicle the check gauge light comes on, stays on and there is a zero oil pressure reading. The engine sounds ok, and it drives fine, and usually if I wait a couple mins it turns off, and the pressure goes to normal. I really don't think it's a problem with the gauge. It only happens when it's colder, and the vehicle hasn't ran in at least 3-4 hours. Today when it turned on, I ran it for a min, shut it off, back on, ran it a min, shut it off, and the 3rd time I started it up, the light stayed off, and reading was ok. It had an oil change right before I bought it, or so the guy said, but the sticker doesn't read it's due for 3,000 more miles, and the oil is clean and up to level. I was thinking maybe it has thicker oil it in? My questions are: What could be causing this? How to remedy it? and does anyone know if the oil filter is mounted sideways? It's been too cold to go crawl under it. I know there are probably lots of reasons I wouldn't be getting a pressure reading, but what would be the best place to start? Like I said it's 2002 XLT, 112,000 miles. Let me know if I left out an info. Thanks

 

[The Rainmayker]

I am not familiar with the circuit that triggers that light to come on, nor with the oil gauge circuit.

How long have you had the vehicle? Have you owned it during periods of warmer weather to know that the cold may be a factor in this situation?

If the oil is flowing properly, as it sounds like it is, there should be no issues. I would think that even if the viscosity was too high, it would still flow enough at startup and would not be enough of a problem to make the gauge stay low. It may be a faulty sensor/sending unit. However an internally collapsed/failed oil filter is not unheard of, especially if you have the "OCOD" (Orange Can Of Death...aka Fram). But I am not here to argue about filter brands, I do that on another automotive site I belong to (BITOG). The filter is mounted directly straight up if you wanted to jack the vehicle up and have a look. Just make sure to have a catch pan in place if you decide to unscrew it.

 

[Cjpooch]

Thanks for the information.

 

[OneLever]

The oil gauge is a dummy gauge. Only moves to "normal" if there's at least 5 psi if I recall correctly otherwise it sits at zero. The oil pressure sensor has been known to get gunked up and send bad readings. If the guy before didn't change the oil frequently then that's possible. Cleaning off the sender has fixed it for some people and some just replace it with a real pressure sender.

What engine type and size do you have? Check the condition and level of the oil with the dipstick often to make sure it's just the gauge. What weight oil was used? I believe 5W-30 is what you should be using.

Also, welcome to the site!

 

[Cjpooch]

It's the 4.0L SOHC. Oil level is good, nice color, oil looks good when I pull the dip stick. I'm not sure what type of oil the previous owner used in it the last time they changed it. So it sounds like you're think it's just a reading problem and there is no actual drop in pressure?

 

[imp]

Knowing for certain whether oil pressure is very slow to "come up" could prevent a disastrous engine failure.....doomsday thought, admittedly.

Placement of a temporarily installed pressure gauge, perhaps with a length of hose similar to a fuel-pressure gauge set-up has, would settle the question of oil pressure.......It could be installed in place of the pressure sending unit.......

Replacing the sending unit is good advice; cost is minimal compared to possible benefit obtained. imp

 

[Cjpooch]

Thanks for all the advice guys. I appreciate it. I'm glad I found this website. I'm sure I'll have more questions in the next few months.

 

[OneLever]

So it sounds like you're think it's just a reading problem and there is no actual drop in pressure?

I do but unless I confirmed it with a real pressure gauge I wouldn't feel comfortable assuming that. As imp said, actually low oil pressure can quickly destroy an engine. These two threads were found by searching "oil sender" on the forum:

Thread 1

Thread 2

 

[Cjpooch]

Ok thanks for the links. I'm still figuring out where I should be posting things, and what threads to look in. Plus I don't know what an oil sender does so I wouldn't have thought to search for that.

 

[OneLever]

It's all good I'm still learning myself. The oil pressure sender just sends a signal to report the the oil pressure.