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I have a Lotus Elise 250 CUP with a 2ZR-FE toyota dual VVTi engine. Running ECU Master EMU Black.
And I have some issues with Intake Cam timing. (Trigger and VVTi settings are from ECU Master base map)
From the Lotus and Toyota Service manual the specs are:
So I supposed to have a 55° room on the Intake Cam to play. But I am only able to advance it 45°. (The Exhaust Cam is moving nicely in the 40° window)
What i am missing here? Trigger setup maybe?
What do you Guys think?
Many thanks in advance!
What have you tried changing? I see there are limits for min/max duty cycle, perhaps it needs more than 70% duty cycle to to reach a more advanced angle. What is the duty cycle when it's at the maximum advance? What is the commanded (requested) position at that operating condition.
Usually I try to plot the CAM angle target and measured angle on the same graph so I can see how well it tracks.
Log that with the duty cycle of solenoid output 1.
I just wanted to test full advanced at 55°. I tried at 100% max duty cycle as well, but not going over 44,5°
On the log the black line is the commanded so 55° and blue is the measured so 44,5°
When I unplug the selonoid, than cam angle is -0.5° so Cam Offset should be ok. So from -0.5° to 44,5° moves the cam 45° ok, but somwhere missing 10° :) Should be operatin range 55° if the service manual correct.
Perhaps someone has installed some range-limiting into the VVT mechanism, this would typically be done if different cams or pistons were fitted. It important that the VVT mechanism can never allow a valve/piston interference -- so even if the ECU programming fails, it can't mechanically hurt the engine.
44 deg is a lot of CAM advance, and is similar to what I've seen in the VVT engines I've worked with.