Ticking Noise Update...ABS Related?

[OK-944]

An update on the ticking noise which seems to pulse at about half the crank speed, and only audible in first or second gear, sometimes while in neutral - at rpm's between 1400 and 2000. Car is an '87 NA. The sound goes away when the brake pedal is applied - and I'm thinking that there might be some sort of erroneous ABS signal causing this. Does this ring any bells for anyone?

[9FF]

I doubt it’s abs related and pressing the brake pedal also affects the vacuum circuit and there is vacuum to a lot of components including fpr, damper and icv all of which can “pulse”.

It seems like you’re getting somewhere though but you’ll need to investigate one-by-one until you find the culprit.