Hey Scotty, I have an 2008 Nissan Frontier SE with the 4.0L V-6. My timing chain tensioner guide broke as they all do. I put a new guide on. Assembled everything back. Started the truck up and for some reason a rod bearing went out and scared the journal on the crank. Tore the whole engine apart changed all the bearings, crank and rod, had crank machined. On first start everything was good. Drove it down the road. After driving a little while I got a P0021 code and I started smelling oil burn under hood. Oil came out the engine somewhere and got on exhaust manifold. Checked the vvt solenoid and it is fully functional., even get voltage from the harness side. I'm only getting the P0021. So I'm guessing I have the timing chain set right since I'm only getting a code bank 2. And only get the fault after driving for a little while. When it does a cold start, the rpms go up to almost 2000, I have read that that is normal for them to get the oil circulating faster. After a couple mins it goes down to 650 rpms. I torn back into timing area and checked everything again. I did find that the o ring for the cam phaser on driver side was damaged a little. Could that be what was causing my code. It was possibly letting oil leak down from the cam phaser, not able to push the lock inside the phaser to let the cam rotate to retard timing. I also do not see where the oil sprayed from. Checked around the head, the vvt, the dip stick tube. Don't know of anywhere else the oil could have come from. Any thoughts will be greatly appreciated.
any trauma to those o rings on the cover that seal to the inside of that gear could definitely cause that code.. for the oil leak I would wash it down and put some dye in the oil to see if you can isolate the leak further
You wentt a lot further than I would have ever gone with that engine. Realize when the timing chain went odds are Pistons at the valves could be cracks on the head and or block. I would never mess with that engine you would have been better buying a junkyard one. You've done all that work and really you have to start all over tear the whole thing down have it might didn't inspect it it's really not worth all that work. Considering there are thousands of those engines laying around a junk yards when they got wrecked ot rusted-out
