Urgent timing help needed.

I think I'm still with mr_guy_mann. Here's an attempt to deal with the perspective by fitting similar ellipses to the end of the crank and the ID of the sprocket, then adding a line through the dot from the center of the ellipse.

Kind of a crude method, but I do think I'm more convinced that tooth ends up between the colored plate and the next one up, rather than between the two pins of the colored plate.

 

Can you reassemble it all and get a good photo clearly showing the crank dot and tooth square in the middle of its colored link, with the top colored links squarely on the cam marks?

What do you expect to see for the VVT-i gear "lined back up right"?

It has a certain range of motion with respect to its camshaft, though it may also have a spring pin that should latch it at the most-retarded position (toothed part turned most clockwise) if you get it to that position.

The exact phase of the VVT-i gear on the camshaft isn't really critical for installing the chain, because you're lining the colored chain link up with the mark on the toothed part.

 

What are you using to measure the cam and crank signals?

A scope with the proper settings will display the actual waveforms. Both sensors are "variable reluctance" type that generate AC voltage pulses as the shaft trigger "wheels" pass close.

Here's what both sensor signals look like on a Gen2. Blue is the cam, red is the crank. In particular, the ECM is looking at the position relation of the cam sensor peaks vs the "signature gap" of the crank sensor.

PS, I would believe the "basic" voltage readings on your device (scope?). 5V "peak to peak voltage" for the cam is about what I show, and 16V ppv for the crank is slightly higher than mine but "ok". I just think that you have too high of a time base to really see things. Try switching to less time per screen (smaller time base).

Here I have 125 milliseconds for the entire screen, which is just over 2 crankshaft revolutions at idle. (You need a very powerful scope to capture enough data to be useful at your 1 second per division - 12 sec per screen).

If there's too much time on the screen (or not enough sample points for the speed of the signal), then you end up with irregular jagged spikes instead of a smooth pattern.



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Valve spring pressure on the camshaft lobes can push things around. Just follow the service manual procedure and put the chain back on.

Then recheck alignment, get a good pic of the crank sprocket. Put the camera down low inline with the crankshaft.

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