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P0521 engine code /check engine light

jleosnow

Full Member
Joined
Aug 30, 2014
Messages
12
Hello all,
I'm chasing a P0521(engine oil pressure sensor/switch circ. range/perf) engine code and was looking for some insight/others experiences.  I replaced the oil pressure switch and filter below it as it seemed to be the logical thing to do given the code.  I reset the CEL and the same code came back within 4 miles of driving the truck.  Oil pressure seems to be at 20-25psi on the gauge, sometimes down to 15 at idle.

And help would be much appreciated!

Thanks,
-John

 
did you change the oil ... I had the same code ... changed the oil ... pressure went back up to around 40 psi and the code was gone after resetting it ...

John
 
Do you know what filter you are running?
I had this same issue and it turned out to be collapsed pleats in the filter limiting flow (possibly what intimidator experienced as well) I only figured this out after doing the same thing you did, replacing the sensor and screen and still having trouble, I then called an acquaintance who is a GM master tech and he said to change the oil and filter too and see if it goes away. If it does, cut the filter open and check it out. I did that and the filter looked like someone stepped on the internals before putting it in the case. I have yet to have any other issues. I have also never run another Purolator filter either.
 
UPDATE:

Vehicle was out of town and it went into "limp mode".  My wife took it to a Chevrolet dealership and they changed the oil and replaced the filter with a PF63 and all is well now.  I was going to do this myself but because of the situation of her being out of town and the fact that it went into limp mode we had no choice but to bring it into the shop.  It was kinda interesting because as soon as she spoke with the service advisor he said that he thought it was probably the oil filter as well and said that GM had a service bulletin regarding this exact same condition.  I went searching and found this(attached).  It isn't for out specific year vehicle(2010 Avalanche LTZ) but certainly seems like it could apply given the listed Silverado vehicles are all AFM 5.3L trucks...

Thank you all for the input, much appreciated!

-John

http://m.gm.oemdtc.com/TSB/SB-10059068-3018.pdf
 
Resurrecting an old thread, but as I pulled the 2013 Black Diamond out onto the road last week the service engine light lit up and I had a code P0521. After reading this thread, I decided to try a quick fix oil change. At first I didn't think the new filter fixed the problem as the service engine light was still on for the 3 mile drive home. Started and stopped the AV a couple of times and still had the light. The next day as I headed out to the garage to have them look at it, I realized that the light was out. Now, two days and 250 miles later it is still good. thanks for the tip.
 
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