I believe the blacktop VVT is a bit different to the silvertop (silvertop just pulls the VVT on where I believe the blacktop controls the amount of variable timing depending on engine conditions.
With my silvertop, the ECU pulls the pin connecting the wire from the VVT valve to ground when the VVT needs to kick in. There is also a 12v feed to the other pin on the VVT valve.
Therefore, to see when my VVT kicked in, I connected an LED (with a resistor in series) to the same pin on the VVT pin on the ECU with the other end of the LED connected to 12v(i.e. 12v - LED - current limiting resistor - ECU VVT pin). When the ECU pulls the VVT pin to ground, power goes through the VVT valve and my LED indicating light showing when it goes on.
Now, this only tells you when the ECU is telling the VVT valve to work. I also put a toggle switch between one of the wires to the VVT valve and the VVT valve so I could switch the valve off after the ECU had told it to switch in and feel if it made much difference. You certainly could feel the difference but it was MUCH less significant than I thought it would be. I did this some time ago but I seem to remember it to have a similar to (though slightly more than) the effect you get from turning the Air Con on.
Wed, 13 July 2005 21:40
