Oil gauge issue

[bresamil]

I have a 2000 Ford Explorer XLS. Mileage almost 135K.

Oil gauge has just started to swing down to L when idling and sometimes it will go between L and midpoint during the drive.

Ford forums addressing this problem say that it is not the oil pump so don't make that $400 mistake.

If the engine can't hold pressure - most likely due to wear and tear and age - but this problem is just starting, how long until it leaves me on the side of the road?

Have any of you experienced this, and if so, what steps did you take to correct the problem?

I cannot afford to buy another vehicle, and will have to scrape up funds to see if this can be repaired. I can't pay for hours of a mechanic to play hit or miss on the repair.

 

[CrashTest]

Bad (or dirty/ corroded) oil pressure sending unit. See attached picture.

 

[bresamil]

Bad (or dirty/ corroded) oil pressure sending unit. See attached picture.

this is a possibility. I'll cost this out. Thanks!

 

[CrashTest]

You can also test your oil pressure gauge. Take of the little wire on the center of the unit in the picture. Stick a paper clip in the center of the connector and touch it to the side of the engine. Turn on the key but don't start the motor. Oil pressure gauge should go all the way to highest position.

 

[MadDogMarine]

I have a 2000 Ford Explorer XLS. Mileage almost 135K.

Oil gauge has just started to swing down to L when idling and sometimes it will go between L and midpoint during the drive.

Ford forums addressing this problem say that it is not the oil pump so don't make that $400 mistake.

If the engine can't hold pressure - most likely due to wear and tear and age - but this problem is just starting, how long until it leaves me on the side of the road?

Have any of you experienced this, and if so, what steps did you take to correct the problem?

I cannot afford to buy another vehicle, and will have to scrape up funds to see if this can be repaired. I can't pay for hours of a mechanic to play hit or miss on the repair.

If engine can't hold oil pressure due to wear and tear, then you are leaking or burning oil somewhere. Are you dripping oil under engine?. Are you burning blue smoke out of tail pipe when you accelerate? Is there a film of oil on top of your radiator fluid?

Clogged oil filter(cheap to replace) is first option.
When oil gets hot it runs like water. Is the engine temperature normal or is it running hot? If hot, possible thermostat or water pump problems.
Also, a change in your idling speed will affect oil pressure. Lower idle speed will cause drop in pressure. Is this auto fuel injected? Possible tuneup needed to bring idle back to normal(800-900 rpm)?
Worst case-piston main bearing wear causing pressurized oil leaking back into oil pan. Some main bearings can be replaced without pulling engine if oil pan can be dropped. Replacing the engine oil with a heavier grade will help for a while but bearings will eventually fail and a you can hear them rattle with a good ear or stethoscope.
A lot to consider, I know.

 

[bresamil]

If engine can't hold oil pressure due to wear and tear, then you are leaking or burning oil somewhere. Are you dripping oil under engine?. Are you burning blue smoke out of tail pipe when you accelerate? Is there a film of oil on top of your radiator fluid?

Clogged oil filter(cheap to replace) is first option.
When oil gets hot it runs like water. Is the engine temperature normal or is it running hot? If hot, possible thermostat or water pump problems.
Also, a change in your idling speed will affect oil pressure. Lower idle speed will cause drop in pressure. Is this auto fuel injected? Possible tuneup needed to bring idle back to normal(800-900 rpm)?
Worst case-piston main bearing wear causing pressurized oil leaking back into oil pan. Some main bearings can be replaced without pulling engine if oil pan can be dropped. Replacing the engine oil with a heavier grade will help for a while but bearings will eventually fail and a you can hear them rattle with a good ear or stethoscope.
A lot to consider, I know.

Fortunately I'm not losing any oil. Temp is staying stable - one of the first things I looked for since an old car had the oil leak issue which led to the temp change which led to dead car.

So with what you've stated, it seems CrashTest's theory may be the right one. I will put in a new oil filter as well as its due for an oil change.

I'll post results as soon as I find someone to help me out with the labor.

 

[aps45819]

Isn't an oil pressure gauge supposed to change with engine RPM?

Every car I've ever had with an oil pressure gauge drops the pressure at idle and increases with engine speed

 

[struggler44]

Isn't an oil pressure gauge supposed to change with engine RPM?

Every car I've ever had with an oil pressure gauge drops the pressure at idle and increases with engine speed

Yep and if it's low on idle more than likely the bearings are worn; could last 100k like that but then again it could throw a rod out the side of the block or spin a cam bearing tomorrow ..........

 

[CrashTest]

Isn't an oil pressure gauge supposed to change with engine RPM?

Every car I've ever had with an oil pressure gauge drops the pressure at idle and increases with engine speed

Yep - engine oil pressure goes up with RPM but so does battery voltage. Remember, modern oil pressure gauges in street cars don't really measure the oil pressure. They use a sending unit that has a diaphram that allows a certain level of electrical signal to pass down a wire and to the gauge on the dash. Some folks refer to moder oil pressure gauges as "idiot lights with a needle" Probably nine times out of 10, the problem is electrical and not with the engine oil pressure. Even a weak battery can mess up what the "gauge" reads. Also, wiring between the sending unit and the "gauge" could be messed up or the "gauge" itself can be messed up. That's why I suggested the test to make sure the wiring between the sending unit and "gauge" was OK.

 

[aps45819]

Yep and if it's low on idle more than likely the bearings are worn; could last 100k like that but then again it could throw a rod out the side of the block or spin a cam bearing tomorrow ..........

I didn't see the OP say she checked the oil level. That would account for a lower than normal pressure

 

[Gilligan]

I have a 2000 Ford Explorer XLS. Mileage almost 135K.

Oil gauge has just started to swing down to L when idling and sometimes it will go between L and midpoint during the drive.

Ford forums addressing this problem say that it is not the oil pump so don't make that $400 mistake.

If the engine can't hold pressure - most likely due to wear and tear and age - but this problem is just starting, how long until it leaves me on the side of the road?

Have any of you experienced this, and if so, what steps did you take to correct the problem?

I cannot afford to buy another vehicle, and will have to scrape up funds to see if this can be repaired. I can't pay for hours of a mechanic to play hit or miss on the repair.

Which engine?

Some can and will sustain near-zero hot-idle oil pressure for about ever as long as it comes up to a reasonable level when driving down the road. Others..won't.

 

[calvcopf]

I had a similar issue with a Ford Ranger 2.3 liter engine, 100k miles. The oil pressure would sometimes drop to low, then build back up. The problem was the screen for the oil pump intake was clogged with debris/gunk. The job required removing the oil pan and replacing that screen.

 

[MadDogMarine]

I had a similar issue with a Ford Ranger 2.3 liter engine, 100k miles. The oil pressure would sometimes drop to low, then build back up. The problem was the screen for the oil pump intake was clogged with debris/gunk. The job required removing the oil pan and replacing that screen.

I knew a fella that added a quart of kerosene to a new oil change. He would let the engine run for a few minutes then change the oil again but leave out the kerosene. That might have helped in your situation??

 

[Baja28]

Fortunately I'm not losing any oil. Temp is staying stable - one of the first things I looked for since an old car had the oil leak issue which led to the temp change which led to dead car.

So with what you've stated, it seems CrashTest's theory may be the right one. I will put in a new oil filter as well as its due for an oil change.

I'll post results as soon as I find someone to help me out with the labor.

I can change your oil in 15 minutes. Let me know.

 

[EmptyTimCup]

Which engine?

Some can and will sustain near-zero hot-idle oil pressure for about ever as long as it comes up to a reasonable level when driving down the road. Others..won't.

I think the rule of Thumb is 10lbs for every 1000 RPM

 

[EmptyTimCup]

you can also switch from 10/30 which is like water to 20/50

[most quickie oil change places use 10/30 for 'Fuel Economy'



I have a buddy, back in the 70s had a 69 Chevy 4x4 with a 292 6 Cyl

before it finally spun a bearing he was mixing in 90wt Gear Lube to keep the oil pressure up

[drove for 3 yrs like that]

 

[Chris0nllyn]

Isn't an oil pressure gauge supposed to change with engine RPM?

Every car I've ever had with an oil pressure gauge drops the pressure at idle and increases with engine speed

Some...yes

Some don't change enough to move the needle.

The oil pump is typically driven by the cam, so the higher speed of the cam, the more pressure (until the pressure relief valve kicks open)

I'm 99% sure it's the oil pressure sensor/sending unit.