[redbird]

What is a vacuum modulator in regard to the zx turbo? what does it look like,where is it located, and what does it do? Is it found on all 81-83 model years? Anybody know? Thanks...

 

[zakaron 79zxt]

This device is located in the front of the engine bay on the side of the AFM... it has 2 circular electrical connectors and 3 vac hose connectors to it. The device itself looks like it has 2 circular saucers on it (which contain the diaphram to create vacuum). What it does: an electric pulse is sent from the control unit and that pulse is converted to vacuum signal which controls the AAC and EGR. The AAC controls idle speed and EGR is used to recirculate exhaust gas for emission purposes mainly. Just follow the vac hose to its respective device on the manifold. And yes all turbo zx's ECCS came with it.
-zakaron