2012 yukon xl 5.3L, drove on a 600 mile road trip. all the way out was fine, I check guages frequently. On the way back home about 250 miles to go i noticed oil pressure dropping to about 10. I pulled over and checked the oil and only had to add 1/2 Qt. used the rest room and came back out and looked all over for leaks and didn't see anything. Started the truck up and pressure was good for about 100 miles and had to pull over and stop the car again. waited a few min and on restart pressure came back up. Did this like 3 times before getting home. Any ideas on something simple before I take it to a shop. I saw a youtube video of someone adding a engine clean product to the oil and running it for 5 min then doing oil change. I got a check engine lite when it started dropping the 2nd time but no serious warnings if there are any for this? I am going now to see what the code is.
low oil pressure long trip
- Thread starter oldskier
- Start date
Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.
Oil pressure sensor and/or filter screen below it, pick up tube o-ring. Could be something as simple as type of oil or filter you are running. This thread is a good read for starters:
@07Burb
IMPORTANT: The Chronicles of Low Oil Pressure by 07burb
Warning: this is a LONG read but may hold valuable information for others experiencing this same issue. This is what I've experienced and what seemed to work for me. Things may be different for you. Let me start from the beginning....there's also an amendment at the end of this post ---In June...
www.tahoeyukonforum.com
Likely the screen. Do the sensor at the same time.
donjetman
Full Access Member
- Joined
- Oct 22, 2018
- Posts
- 1,984
- Reaction score
- 3,637
Do the sender and screen
Mollys70
Member
Same thing happened to my 2013 Sierra 5.3. New sender fixed it.
Says "sensor switch"? What code says that? What code was it? Codes give you system faults areas and the rest is diagnosis.
Last edited:
That's exactly the behavior I experienced when the sender went out on my 2012 back in 2018, shortly after I bought it. Pressure would be fine for the first 30-45 minutes of a trip and then start to drop until the low oil pressure warning tripped. Replaced the sender and screen and never had another problem.
P0521 - Engine Oil Pressure (EOP) Sensor Performance
To be clear. That means there is a problem found in that "system" but not necessarily the sensor itself. Could only be the screen but no one replaces the screen without changing the sensor and screen Could also be wiring to sensor and 10 new sensors/screens would not fix it. Could also be a oil pressure problem. Lots of choices but the %'s usually are the sensor and screen.
Charlie207
Full Access Member
I also recently had this issue of pressue reporting very low via the dash gauge. I did the following procedure during an oil change with filter removed.
I would start by pulling the sensor and screen, and cleaning out the orifice/hole in the sensor really good with brake cleaner and a soft pick of some sort. Reinstall the sensor with no screen; it's probably trashed now anyways from getting it out of the engine block. (You want to eliminate variables of the screen to see if it's just a clogged sensor orifice.)
Blow out the sensor hole in the block with air or brake cleaner to get rid of the tiny gunk.
Reinstall the sensor, finish oil change, and go for a drive.
Pay attention to the pressure level, and how much faster the dash gauge responds to engine load & RPM.
If there is a big change/improvement, then it was probably a gunked-up screen and sensor, like mine. Pulling out the screen and blasting out that tiny orifice in the sensor instantly fixed the reporting problem.
Here is my socket setup using the "OEM Tools" sensor socket from AutoZone (or O'Reilly's):
It's a 10 minute job now to get the oil pressure sensor out/in after doing it once before to replace it (which didnt really solve the low psi issue last year).
Pull engine cover.
Unplug vacuum hose from brake booster, and tuck it to the left of the engine, out of the way.
Reach back and unclip sensor harness. Pinch one side of harness and wiggle up. Move harness & cable to the left of everything.
Place socket (3/4 drive), u-joint, and 3/4 > 3/8 adapter onto sensor as one unit. Attach 6" 3/8 extension and ratchet, and give it a crank to loosen. Once loose, you can remove extension and socket, and hand-loosen the sensor.
It's tight, and you'll do some planks on the radiator support to reach it, unless you can convince a small child to sit up there and route all the stuff & things, so you only have to mash the ratchet to loosen the sensor.
I would start by pulling the sensor and screen, and cleaning out the orifice/hole in the sensor really good with brake cleaner and a soft pick of some sort. Reinstall the sensor with no screen; it's probably trashed now anyways from getting it out of the engine block. (You want to eliminate variables of the screen to see if it's just a clogged sensor orifice.)
Blow out the sensor hole in the block with air or brake cleaner to get rid of the tiny gunk.
Reinstall the sensor, finish oil change, and go for a drive.
Pay attention to the pressure level, and how much faster the dash gauge responds to engine load & RPM.
If there is a big change/improvement, then it was probably a gunked-up screen and sensor, like mine. Pulling out the screen and blasting out that tiny orifice in the sensor instantly fixed the reporting problem.
Here is my socket setup using the "OEM Tools" sensor socket from AutoZone (or O'Reilly's):
It's a 10 minute job now to get the oil pressure sensor out/in after doing it once before to replace it (which didnt really solve the low psi issue last year).
Pull engine cover.
Unplug vacuum hose from brake booster, and tuck it to the left of the engine, out of the way.
Reach back and unclip sensor harness. Pinch one side of harness and wiggle up. Move harness & cable to the left of everything.
Place socket (3/4 drive), u-joint, and 3/4 > 3/8 adapter onto sensor as one unit. Attach 6" 3/8 extension and ratchet, and give it a crank to loosen. Once loose, you can remove extension and socket, and hand-loosen the sensor.
It's tight, and you'll do some planks on the radiator support to reach it, unless you can convince a small child to sit up there and route all the stuff & things, so you only have to mash the ratchet to loosen the sensor.
Last edited:
I agree with Charlie but caution against removing the screen in an engine that still has active AFM components. As I understand it (which could be wrong), that screen plays a role in protecting the tiny oil passages in the VLOM and lifters from debris. In an active AFM engine, I would replace both the sensor and screen.
Charlie207
Full Access Member
I agree with needing a screen if AFM is still active.
If you need a quick way to troubleshoot, I would hope 5 minutes of driving wouldn't hurt the system with a missing screen, especially after a fresh oil & filter change.
