Just wanted to get some insight here to see if there is something I'm missing. 2006 LBZ truck. Long story short, hole in one piston and had a shop do all the machine work and put the longblock together. Went with the Mahle 0.20 rebuild kit and had to sleeve one cylinder. GM C grade head gaskets. New GM cam, new oil pump, surfaced the heads, valve job, with new seats and guides. Injectors were all bench tested and good. Turbo was completely rebuilt with new sensors and solenoid. New glow plugs, flushed old fuel from lines and tank. Idhao Rob tunes.
Initial startup was rough and shaking the while truck. Let the truck run for maybe a minute or two and shut it down. Here's the checklist so far.
-Checked and verified fuel pressure from lift pump. Pressure was 10psi.
-Checked fuel pressure regulator operation and verified that high side fuel pressure was within spec.
-Checked injector balance rates.
-Removed serpentine belt and ran engine to ensure that the problem wasn't imbalance from the fan clutch or any engine accessory.
-Replaced harmonic balancer to eliminate engine imbalance issue.
-Scanned ecm with tech 2. Verified no codes and cam and crank sensor operation.
-Removed all glow plugs and Performed compression test on all cylinders. All cylinders tested at 350 psi with 6 revolutions of the engine except #4 cylinder. #4 cylinder tested at 325psi.
-Got #4 cylinder on top dead center. Ingested smoke into the cylinder. Smoke immediately came out of the intake.
So on a new engine, does this indicates an intake valve issue on the #4 cylinder or is there a potential problem somewhere that I'm missing??
Initial startup was rough and shaking the while truck. Let the truck run for maybe a minute or two and shut it down. Here's the checklist so far.
-Checked and verified fuel pressure from lift pump. Pressure was 10psi.
-Checked fuel pressure regulator operation and verified that high side fuel pressure was within spec.
-Checked injector balance rates.
-Removed serpentine belt and ran engine to ensure that the problem wasn't imbalance from the fan clutch or any engine accessory.
-Replaced harmonic balancer to eliminate engine imbalance issue.
-Scanned ecm with tech 2. Verified no codes and cam and crank sensor operation.
-Removed all glow plugs and Performed compression test on all cylinders. All cylinders tested at 350 psi with 6 revolutions of the engine except #4 cylinder. #4 cylinder tested at 325psi.
-Got #4 cylinder on top dead center. Ingested smoke into the cylinder. Smoke immediately came out of the intake.
So on a new engine, does this indicates an intake valve issue on the #4 cylinder or is there a potential problem somewhere that I'm missing??
