Saturday, June 19, 2010

How to Build a Lift Controller for VVTLi (2ZZ-GE)

The lift controller is comprised of few simple components.

1. An RPM switch - which used an MSD 8969 Digital window switch Found Here.

2. A VVT/VVL solenoid - any solenoid from 1ZZ or 2ZZ

3. A micro switch - Anything that is SPDT or SPST that is NC and C.

These are the 3 things needed. Now if you want to make some extra power, it would be nice to control the cam phasing (VVT-i) with something like a PE Camcon.

Theory of operation.

The VVL system appears to have a current loop to sense if the VVL solenoid is presend. The attempt at using a simple relay failed as it could not properly mimic the properties of a solenoid through a relay. Instead, using another VVL/VVT solenoid (both are the same manufactured, different is how it works. VVT is pulsed duty, VVL is on or off) and taken the oil valve assembly apart with a simple flat screw driver, then re-sealed the unit by hammering the tabs back on. A bracket (out of wood or whatever) and spaced the micro witch so that when the ECU activates the VVL solenoid (6300 for 03, 6500 for 04), the micro switch then removes the ground and the ECU thinks all is well.

The OSW looks for an OPEN when lift is engaged, not a short to ground. Be sure to use the NC contact on your micro switch. If you don't, you will get a CEL and you will not be able to rev over 7000rpm.

Now that the ECU is separated from the VVL solenoid on the engine, we can now simply activate the solenoid throguh the RPM switch. Back feed to the ECU is NOT an issue because they are separate.

Simply connect the ground switching RPM switch's NO contact to one side and put +12V to the other side. Polarity is not an issue.

- OVL(+) and OVL(-) go to your separate VVL/VVT solenoid that you have fabricated with the micro switch.
- OSW goes to the ->NC<- contact of your micro switch and the C goes to ground.
- The component side OVL + and - (the non ECU side) got to 12V Power and the NO contact of your RPM switch.

Remember, I wrote this for a ground switching RPM switch. I do recommend the MSD 8969, its digital, it set up and worked great. (Credit to Nolat)


This looks really cool. Have you tested this, does it work, I want to do this,
Do you think you can email me a larger version of that diagram? at

Also do you mind if i repost this on Spyderchat forum?

Hi Nikita,

I do not have a larger diagram for this. No problem, do share it out among the VVTLi users

It doesn't work without a camcon or some other form of control of the cam phase angle

Have you tried this Tom ? or are you assuming ? I know of a car in SA that done this and it working...

by doing this do u have 2 use a cam con to set d vvti cam degree???? or does the vvti sprocket keeps working as normal??