Shmitt

Pulled apart my top end a bit and discovered slack in the chain between cams, I then turned the crank to the timing mark and saw that the notches are misaligned, also discovered that the upper guide is grenaded..as suspected it gave way finally. My question is, could any valve damage have happened? A local shop said I was getting 250-255 across all 6. My concern was the aweful sound when it was running on the lower 3, sounded like something tapping really hard. TIA

Pulled apart my top end a bit and discovered slack in the chain between cams, I then turned the crank to the timing mark and saw that the notches are misaligned, also discovered that the upper guide is grenaded..as suspected it gave way finally. My question is, could any valve damage have happened? A local shop said I was getting 250-255 across all 6. My concern was the aweful sound when it was running on the lower 3, sounded like something tapping really hard. TIA

So indeed no power to the top bank of injectors, what might cause this? I'm starting to wonder about the ECU or harness to and fro? Thanks for the help..

I will try all of those things, I am leaning toward injectors too or something that controls the top 3. Others have also suggested checking the cam position sensor, but I think that would throw an error code and I doubt the engine would run at all?

2000 Jetta VR6 Had a shop look at it, cylinders 1,3,5 are not firing. Plugs all get spark..mechanic noted that the rear 3 seem to have heavier spark than the front 3, compression checks out at 125 across all cylinders. Nothing came on during the scan and mechanic believes there is nothing mechanically going on with it. Changed out coil pack and wires before he had a look, made no difference...help! This all occurred from one start to the next, running perfect to this 2 hrs later..I'm stumped