'06 Sierra 5.3L smokey startup fixed

Marc Ohmann · July 9, 2022

My '06 Sierra with the 5.3L and 220k miles has been using 1-2qts oil between oil changes for years and recently started fogging the area in heavy blue smoke on startup. Until today. I pulled the driver's side valve cover to clean the PCV baffle and drill some new drain holes. After getting it off, I see it already had two additional drainage slots cut in so i just cleaned it excessively. The baffle was caked in tiny chunks of gunk. I ran a couple quarts of pressurized diesel through it with endless chunks draining from the tiny baffle holes until it was finally as clean as it was gonna get. One test drive with 4 starts and no smoke! Excellent!

It even cleared the P0053 O2 sensor code it recently threw and it runs more smoothly at startup and shutdown. However it is better but still a little rough at idle. I'm guessing the original plugs could use a changing after all these years of oil consumption. If that doesn't do it maybe an intake gasket is in order.

New oil pump pickup o-ring and now cleaned valve cover and she's almost a new engine ready for the next 200k.

dna9656 · July 9, 2022

I put a new O ring in my 06 5.3 and the lifter noise (presumably from pump cavitation) ceased. I replaced a valve cover (driver's side) because there was a defect in the OEM design (something you should into); the T chain and sprockets, installed a HI Vol (Melling) oil pump, oil level sensor, t chain cover (because Haynes said to) oil pick up tube. I didn't want any part not replaced to turn "weak" and have to disassemble the job to replace some thing I "should have" replaced.... I even filed the casting spatter from inside the oil pan!

BTW how does one "clean excessively" anyway:)

Marc Ohmann · July 10, 2022

Yeah, "extensive cleaning"or "exhaustive cleaning" are probably more accurate. The crap just kept pouring out of those little seep holes in the baffle -- amazing how much was in there.

At one time, I thought I had lifter noise but it's just the broken exhaust manifold bolts. I have 40-60psi now after replacing the o-ring so not too worried about replacing the pump yet. After having the oil pan off and seeing how clean everything was, I'm encouraged to maybe take on rocker panels and fenders next year and get her back to looking like new. I last did rockers on my '87 and that was a long time ago. I have a lot more patience for that type of work now and I think it'll actually be fun (or at least rewarding).