waypoint
Member
The extra diameter of the idler gear would decrease slack in the chain, not add more. Visualize the radius of the gear, as the distance from the idler gear bolt downward. A larger radius (1/2 diameter) would move the chain downward, away from the intake camshaft sprockets...lengthening the travel path of the chain and reducing slack.
Here's my thought: you verified that the lock pin was locked. This pin locks the intake cam in maximum retarded position until pressurized oil unlocks it and fills the VVT chamber, causing the vane (which is bolted to the cam) to advance the cam.
We know that a stretched chain causes P0016 consistently. There's no evidence I found of a P0012 from chain stretch.
We know from the shop manual that P0012 is a dynamic test by the ECM as the OCVs are actuated, and results when the cam does not advance to the expected position relative to crank position.
So...I'm thinking the actuator pin may not be unlocking. Again, the engine had this error code before all the new timing components were installed. I'd install a new Toyota VVT actuator/sprocket assembly at this point.
As far as your visible timing retard at the intake cams, what brand was your timing kit? Possible that this was a chinese knockoff and the crank sprocket and/or main chain are not to spec.
Here's my thought: you verified that the lock pin was locked. This pin locks the intake cam in maximum retarded position until pressurized oil unlocks it and fills the VVT chamber, causing the vane (which is bolted to the cam) to advance the cam.
We know that a stretched chain causes P0016 consistently. There's no evidence I found of a P0012 from chain stretch.
We know from the shop manual that P0012 is a dynamic test by the ECM as the OCVs are actuated, and results when the cam does not advance to the expected position relative to crank position.
So...I'm thinking the actuator pin may not be unlocking. Again, the engine had this error code before all the new timing components were installed. I'd install a new Toyota VVT actuator/sprocket assembly at this point.
As far as your visible timing retard at the intake cams, what brand was your timing kit? Possible that this was a chinese knockoff and the crank sprocket and/or main chain are not to spec.
