swathdiver
Full Access Member
Well, come to think of it, I think mine has seen 208 before, it's a calculated number, we don't have an actual sensor. Anyhow, your oil pressures are high for an aluminum motor, or your gauge is off.
P0521 Code
- Thread starter Mickey_7106
- Start date
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Interesting. I've tried that one but no joy. Might be an NBS thing, but mine is FF so I know it's there somewhere.
OP
OP
Mickey_7106
Full Access Member
i'll like to take a manual reading but i m not sure how. my '06 Silverado drove the same PSi. Even after switching a bad oil pressure sensor.
swathdiver
Full Access Member
Well, high is better than low! Not sure where to plug in a manual gauge either.
FWIW-I had this P0521 code on my rig about 2 weeks ago. I confirmed that it was not an oil level issue so began researching. Found several articles and videos about changing the sensor on the back of the intake near the firewall. Purchased the sensor, filter, and socket from Amazon (AC Delco sensor) and set out to replace. I am in no way a mechanic but got it all swapped including oil change after about 3 hours. Total cost in parts was $75 which included 6qt of synthetic oil/filter and sensor items. This resolved my code issue but still see about 28psi cruising down the highway at 1800rpm.
indy
TYF Newbie
- Joined
- Jul 15, 2012
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Just want to report on my '07 5.3L that at 130k miles I got the P0521 low oil code while highway driving in 5 degree weather (which this Tahoe has never seen). At highway speed at 2k RPM the oil pressure slowly dropped down to ~18psi at lowest. 2300 miles on current oil. After reading forum I assumed I was ok to continue trip.
I run Mobil-1 synthetic 5-30 and any mid-grade filter changing oil 4-7k miles.
I decided to run Seafoam for last 200 miles (no help in dash pressure). Added cheap quart of oil and pointed rig down hill to verify oil pickup oring in pan was ok, then change oil / filter before jumping into the new oil pressure sending unit and screen.
HAPPY TO REPORT: Simply drained oil and replaced old STP Extended Life Oil Filter S10060XL with WIX 57045XP oversize filter and fresh Mobil-1. Boom...instant oil pressure just from new filter so I assume filter was faulty or clogged.
Low pressures indicated in park: Idle 17psi, 2k 22psi, 3k 33psi
After oil/filter change pressures indicated in park: Idle 32psi, 2k 47psi, 3k 53psi
FYI. I added oil catch can so now I'm going to send out ECM to remove AFM V4 function as CYA.
I love this forum. ♥
I run Mobil-1 synthetic 5-30 and any mid-grade filter changing oil 4-7k miles.
I decided to run Seafoam for last 200 miles (no help in dash pressure). Added cheap quart of oil and pointed rig down hill to verify oil pickup oring in pan was ok, then change oil / filter before jumping into the new oil pressure sending unit and screen.
HAPPY TO REPORT: Simply drained oil and replaced old STP Extended Life Oil Filter S10060XL with WIX 57045XP oversize filter and fresh Mobil-1. Boom...instant oil pressure just from new filter so I assume filter was faulty or clogged.
Low pressures indicated in park: Idle 17psi, 2k 22psi, 3k 33psi
After oil/filter change pressures indicated in park: Idle 32psi, 2k 47psi, 3k 53psi
FYI. I added oil catch can so now I'm going to send out ECM to remove AFM V4 function as CYA.
I love this forum. ♥
Last edited:
swathdiver
Full Access Member
What's the other one for? 55488247?
The sensor on the 2013 6.2 Sierra died last night, no AFM.
I have to take the intake off as well and don't want a surprise.
Bummer about the sensor :-(
I don't remember now which reference source I used to make that call for his truck but it was probably one of the GM parts houses. Probably the best way to be sure which connector you have is to get some fingers back there to feel whether it's flat or round. Or buy one of each and return the one you don't need.
swathdiver
Full Access Member
I bought both. Every website I use showed both and I wasn't about to dig through the garage to see where the kids put the step I built to work on these things. I'm still recovering from surgery, they'll be doing the work at my direction!
