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GM 3.6 VVT

So I can offically confirm that the timing marks are off. All back together and running better than ever. When I first got it back in and started it it ran like crap. Had 3 codes one for knock sensor circut one for cylinder #3 misfire and one for map sensor. I called it a day at that point, came back out this morning and after thinking about it I decided to check the knock senor by the CKP sensor. Sure enough I had failed to plug it in, not an easy reach to get it plugged in either. Fired it up again and it still ran like crap so I pulled the #3 coil and sparkplug. Did a compression check while I was there just to make sure nothing mechanical was going on. 150 psi with only that one plug removed. Swapped coils with another cylinder and it didn't make any difference except now I just had a generic code for misfire. Borrowed my buddies scanner and it showed that cylinder 3 was still the one misfiring so I bought a sparkplug and put that in. Got rid of the code but still ran like crap, was in the process of starting to remove the intake manifold to look for a vacuum leak when I noticed a hose that didn't appear to be connected. It wasn't until I removed the upper half of the aircleaner and the intake tube that I saw it. Pretty hidden once everything was in place, turns out it was the hose going to the brake booster. Only a minor vacuum leak! (insert face palm here). Once I fixed that it purred like a kitten.
 
ak diesel driver said:
So I can offically confirm that the timing marks are off. All back together and running better than ever. When I first got it back in and started it it ran like crap. Had 3 codes one for knock sensor circut one for cylinder #3 misfire and one for map sensor. I called it a day at that point, came back out this morning and after thinking about it I decided to check the knock senor by the CKP sensor. Sure enough I had failed to plug it in, not an easy reach to get it plugged in either. Fired it up again and it still ran like crap so I pulled the #3 coil and sparkplug. Did a compression check while I was there just to make sure nothing mechanical was going on. 150 psi with only that one plug removed. Swapped coils with another cylinder and it didn't make any difference except now I just had a generic code for misfire. Borrowed my buddies scanner and it showed that cylinder 3 was still the one misfiring so I bought a sparkplug and put that in. Got rid of the code but still ran like crap, was in the process of starting to remove the intake manifold to look for a vacuum leak when I noticed a hose that didn't appear to be connected. It wasn't until I removed the upper half of the aircleaner and the intake tube that I saw it. Pretty hidden once everything was in place, turns out it was the hose going to the brake booster. Only a minor vacuum leak! (insert face palm here). Once I fixed that it purred like a kitten.
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Thats some good news.
If ever the wifeys 08 Maliblue needs some engine work, I’m bringing it over to You. 😹😹😹
 
ak diesel driver said:
So Cloyes recieved my old timing set and are sending me a new set. Only parts I'm waiting on after that is new head bolts. Ordered them a week ago on Amazon still haven't shipped yet
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I would get hold of Cloyes again. Offhand I would ask if the colored link on the timing chain is one link pin off?

I would call them before it possibly bends the valves again.

As you noted the engine somehow ran for 150K so we can assume it's ok for key way locations etc. Hopefully GM doesn't have a splash of paint to factory correct machined screw ups on timing somehow.
 
Technically, an idler gear has absolutely no affect on timing. It's called an idler because it sits there idle and does no work when rotsted by the chain running over/around it. An idler serves one of two functions, or both. It takes up slack in a chain (if spring loaded to do so, it's then called a tensioner) or changes a chain's direction as it continues on to a sprocket that drives something to either make the drive more compact or to improve the angle of entry/increase contact of the chain onto a driven sprocket. In the case of your engine, those idlers both make the drive path of the chain more compact and increases the engagement contact between the cam sprockets and the chain.

The only way you would affect timing between the crank sprocket and the cam sprockets would be for the timing mark(s) or keyway(s) to be off on any of those three sprockets or for the timing mark(s)/link(s) on the chain to be off.
 
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