Now here's where it gets interesting. On page EC-116 of the FSM, nowhere in the VVEL control flowchart does it mention oil temperature. A misprint? I doubt it. Most people associate the high oil temps with the VVEL system.
I'm no expert but i think it's the intake valve timing control system that's the cause of the oil temperature related lag. As oil gets hotter, it gets thinner. The CVTC system on our engines uses hydraulics to advance or retard the intake valve timing. The hydraulic fluid is the engine oil, directed thru the ECU controlled passages by way of oil control solenoid valves. Thin oil results in lower hydraulic pressure. Now, the system does have a self checking feature which relies on the cam angle sensor. There is a threshould until a DTC is flagged though, so all our experiences might just be within that tolerance.
On some makes, there is a screen filter on the solenoid but i'm not sure if ours have any filter.
Page EC-107 of the FSM lists the oil temperature as a parameter in the CVTC control system. Sluggish response on VVT engines is commonly associated with the oil control valves or lack of hydraulic pressure whether it's due to low oil level, blockage or whatever.
Another factor in this lag equation is the ECU software, which is known to be conservative and overprotective.
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