I think that a great amount of emphasis about the importance of using a
PASSIVE CHEMICAL SOLVENT CLEANING OF THE OIL PICK UP TUBE AND LOWER CRANK-CASE-OIL-PAN deserves to be shown...pictorially...so you can better understand the consequences of what will happen if so much Carbon and Ash Residue Buildup inside of your Ecotec Engine ...FLAKES OFF THE ENGINE BLOCK AND COMPONENTS AND GETS SUCKED UP INTO THE OIL PICK-UP TUBE SCREEN.
These images are edited Screen Snaps from some Youtube Videos of
@Kevin Nadeau 's Excellent (5) Part R&R Series of his FUBARed Oil Pan and Oil Pick-Up Tube ...WHICH HE BELIEVED WAS NECESSARY TO PERFORM ...
AFTER HIS OIL PICK UP TUBE WAS COMPLETELY CLOGGED AND BLOCKED ...AND THEN HIS ENGINE OIL PRESSURE WENT PRACTICALLY DOWN TO "0":
What seems quite unfortunate to me now is that ...upon reflection... He probably could have accomplished all of the work he describes in his Five Part Series... by simply Draining the Motor Oil from his Crank-Case-Oil-Pan...and then filling it up with around 2 or 3 Gallons of GUNK Carburetor Cleaner. Then after allowing the Motor to sit for a Day or so...Passively Soaking into and Removing all of that Brown-Black Carbon-GAS-GUM Mung until it dissolved the entire Mess... Right Down to Bare Metal.
After that, it would have been a simple matter of removing the Oil Drain Plug and allowing all of the Mess to thoroughly Bleed out of the Engine... followed by performing a Proper Engine Flush Procedure and installing a Mobil1 Oil Filter and Mobil1 5W-30 Motor Oil. Hind Sight always being 20-20.... Then NONE of the Complicated, Mechanical Repair Shenanigans Kevin had to do would have been necessary!
After observing the Color and Condition of Kevin's Munged Up Oil Pan and Oil Pick Up Tube ...and comparing how much WORSE that stuff looks on the Vertical Wall at the Front of your own Engine... Perhaps You should think about this reality being present in your Lower Crankcase and stuck to your Oil Pick Up Tube. You can try Test Cleaning the front of the Engine up... Perhaps using the GUNK Carburetor Cleaning Product Kevin used instead of the Berryman's stuff... and then watch how all of that Brown, Caked On Crap... just dissolves away.
You can Bet Good Money Against Bad that the Prime Reason that your fairly Youthful Engine has
SO MUCH CARBON BUILD-UP in the Bottom End and Elsewhere, is because all of the Compression Rings on the Pistons of your 4 Cylinder Engine are probably
GAS-Gummed Up and STUCK FAST inside of the Piston Grooves... causing a Hellatious Amount of Combustion Blow-BY. THAT Problem can be solved by using ACDelco's Top Engine Cleaner (TEC)... but that Topic is very well discussed and covered in Other Threads :