OK folks, here's my story on the P0521 code. CEL light comes on so I call to schedule an appointment as it was a certified used. They tell me code P0521 (oil pressure sensor) and they replaced the sensor. I picked it up and drove it for a couple of days equaling about 40 miles and the light comes back. I call them and schedule for the next day. They call me telling me that the screen below the sensor had been clogged so they replaced it. Drove it for about 30 miles and the light didn't come back for them. I picked it up and it was back on by the time i got home. I also noticed that my oil pressure was about 18 when sitting at idle. today they tell me they did oil pressure tests and some other diagnostics and while on the phone with GM tech they replaced the PF48E filter. Fired it up, oil pressure is holding steady at 38 and is to temp. They will keep it all day tomorrow to drive it to be sure. I read with a little googling that the cars originally meant for PF48 filters and switched to PF48E filters are not liking them...Does anyone have any experience with this?

Update:

So, after picking it up from the what was thought to be a bad oil filter, i drove the truck about 500 miles till the light came back on. The oil pressure had been slowing edging lower and lower over the 500 miles. I took it into the dealer Wednesday night and they called me thursday. GM wants the engine torn down because they found metal in the oil. At this point, I'd almost rather get a new engine. But, since it's a certified vehicle, I'm not sure how much of what I say matters. does anyone have any thoughts or experience with failure of a 5.3L @ 60,000 miles?

 

Well, I got the call this morning. GM has authorized a NEW engine. The dealer I have been working with has been great. I suppose this is best case scenario?

 

WOW!

I can't believe they did that! Usually I hear nothing but horror stories

 

Honestly, I wasn't expecting them to either. I was fully expecting to have to fight with someone. The service manager told me that if the cylinder walls are scarred is usually the only way they authorize a new one. I haven't gotten the full details on everything that was 'wrong' but i'm guessing they found enough to warrant the new one. And hey, I got to drive some cool new stuff in the process!

 

That's impressive.

I can't believe I hadn't chimed in on the oil filter thing ... I heard a big fuss go around about those oil filters possibly causing oil pressure issues ... I personally never experienced that.

It's hard to believe they're installing a new engine. Unless there's damage to the block its self in an area that's not fixable (See: scored lifter bore, scored cylinder wall, broken/leaking casting).

 

Once I find out the list of what the issues were I will update everyone.