Mechanic question - 2011 F-150 5.0L Low oil pressure light comes on at idle in gear

[BigL]

Happens often but is really random. Doesn't matter if it is after an oil change or needing to be changed. Just the warning light when in gear and going to a stop. Will stay at 0 pressure on guage in dash until time to go. Put in neutral back to normal. Keep idle around 600rpms+ and no warning. Let it drop to 500 and light may come on. Idles fine no noise but guage at 0.

Any idea?

[RifleBowPistol]

You have low oil pressure, gauge ain't lying to you. I would not drive it and have it checked soon. Have someone hook a manual gauge to it and see what it drops to, when warm and in gear. I would bet 10 psi or less.

There are multiple possibilities of what is causing the problem. I think I have heard the gen 1 coyotes have oil pump problems. But if the oil pressure is low, I would check the rod and main bearings, and the pick up screen, before putting it back together. Also overhead cam engines, or at least the Ford mod motors would often lock up the cams in the heads. The coyotes are about gen four mod motor engines in reality. I would also check the cam journals, to make sure those don't have any sign of wear, before calling it good to go.

But there will probably be guys that tell you just put a pump in it and it will be fine, it may be, but I would not trust that on my engine. Anytime the oil pressure is low, you are going to have parts wearing.

[Rem40x]

Mine is diesel same thing. Let it idle and remove the oil fill cap of it has psi on it like mine they had to changed crank case breather simple fix 30 min job

[Big Lee]

If no noise. Very well can be a oil pressure sending unit or instrument cluster issue. What is the oil pressure reading while driving?

[cva34]

If no noise. Very well can be a oil pressure sending unit or instrument cluster issue. What is the oil pressure reading while driving?

oil pressure sending unit...its a cheap date and easy fix and or test...

Getting at can be another story...some easy peasy ,,,some finding and getting to can be a nightmare..I'm not familiar with yours ...you can plumb in a mechanical gauge..for test too.

[Samson]

oil pressure sending unit...its a cheap date and easy fix and or test...



Getting at can be another story...some easy peasy ,,,some finding and getting to can be a nightmare..I'm not familiar with yours ...you can plumb in a mechanical gauge..for test too.

This, it's the sending unit. Mine had a real slow leak and would do exactly as you describe. The sending unit is plumbed in to the oil pan on the driver's side. It took about 300 miles of driving to make the light go away once the unit was replaced. I'm guessing because air got in there when I replaced it. So don't be disappointed if the light doesn't go immediately away. Mine is a 2012 5.0.

Sent from my TA-1004 using Tapatalk

[BigL]

oil pressure sending unit...its a cheap date and easy fix and or test...

Getting at can be another story...some easy peasy ,,,some finding and getting to can be a nightmare..I'm not familiar with yours ...you can plumb in a mechanical gauge..for test too.

Yea mine is behind the alternator. Pain in the arse to get to. Pretty sure my big hands can't get in there so I'll need to remove the alternator. Mine has a slow leak there as well. Is it worth replacing the wire and/or the connectors since they probably got oil in them or will a good cleaning do the trick? While I'm there I may replace the oil level switch too.

I have 207k miles on this truck. I bought it used at 50k miles. I've changed the oil every 5k.

[oktx]

I just talked to my dad. His is doing the same exact thing.

[BigL]

I just talked to my dad. His is doing the same exact thing.

Seems to be a common problem after a quick check on the F150 forums. Problem with those forums is that a lot ask the question but never come back to say what was the fix.

[eagles405]

I have had to replace the sender unit twice over 3 years on my 2013 f150. Same thing as you describe. Pain in the tail to get to under the alternator on my 5.0 engine

[oktx]

Seems to be a common problem after a quick check on the F150 forums. Problem with those forums is that a lot ask the question but never come back to say what was the fix.

My dads is a 2011. He’s going to change the sender.

[BigL]

My dads is a 2011. He’s going to change the sender.

That's my plan too. It's just in a bad place to get to it so may be taking it to a local shop to do for me.

Sent from my Moto G (5) Plus using Tapatalk

[oktx]

That's my plan too. It's just in a bad place to get to it so may be taking it to a local shop to do for me.

Sent from my Moto G (5) Plus using Tapatalk

Several videos on YouTube, doesn’t look too bad.

[BigL]

Several videos on YouTube, doesn’t look too bad.

Those are 2wd. The 4wd you need small hands and a lot of patience for things like this. I don't have either. Or be willing to take the alternator off. I'm not cause that would wear on my patience of who the hell designed it this way.

I'd rather not use my free time on the weekend to do it. Much easier to drop off in the morning and pick up when I get off work and use the weekend for dove hunting.

Sent from my Moto G (5) Plus using Tapatalk

[Twist]

If no noise. Very well can be a oil pressure sending unit or instrument cluster issue. What is the oil pressure reading while driving?

Very likely this.

Get a new sending unit as soon as possible and see if it fixes the issue.

If you were actually experiencing truly low oil pressure you’d likely already know it and would have found out in a not good way. It’s probably just a voltage issue between the relay and gauge but definitely be cautious about it.