VDI Help

[NoDOHC]

The VDI (the actuator on the intake manifold) requires the car to be driving to operate. IT is controlled by the ecu using a solenoid valve. If this valve fails or the air pump that supplies the pressure to operate the VDI fails, you have no VDI. A lot of emissions removal schemes end up going awry and costing 25ish Hp by making the ports and VDI disfunctional.

There are several fitment threads in the wheel and tire section, but the short story is that you will have to roll the fenders to run 17X9s, the 17X8s fit ok.

[Rotary Related]

Originally Posted by 89fc3s

my VDI doesnt work emissions are intact. How do i narrow down the problem?

and i know 17x9 will fit just will it fit with the offset?

First check the vacuum hose that supplies pressurized air from the ACV to the 6PI and VDI solenoids. It is located on a nipple just behind the main large hose from the airpump and comes out perpendicular.

Follow that hose. When you get to the rear of the engine where the smog racks are bridged by vacuum hose that's where a hose is probably broken or fallen off.

Next move to the solenoid side of the engine. If the ignition is on and engine not running you can use a probe and ground the colored wire (Not the black wire that is a power wire. It has a white or yellow stripe.) of the VDI solenoid and you should hear an audible click when it opens. If no click then you either didn't get a good ground or your not getting power from the ECU to the black wire on the solenoid. Check for 12V on the black wire if this happens.

Check all the hoses you can get to. Basically the air travels out of the nipple at the ACV through the rack then splits and feeds both the VDI and 6PI solenoids. then out of the solenoids and to their respective diaphrams to open the ports or VDI.