Hey, I just got a 1983 Aria Pro II (its my second guitar) with dual humbuckers, coil tap, and a phase switch. I did a thorough cleaning yesterday and I tried get some of the rust off my pickups with a little WD40 and I pulled both pickups out to clean behind them, you know the whole deal and stuff, but when I put everything back together the bridge pickup sounds at less than half as loud as the neck pickup and kind of crappy.

I tested the poles with a metal allen wrench and the neck pickup has a fat popping sound but the bridge has a thin, 1/2 or 1/4 as loud pop.

The pickup height is the same as it was before and if I raise the bridge pickup it doesn't make much of a difference.

Help! I've tried flipping the pup, cleaning its parts again, etc. but I can't figure out what did it.

Is the WD40 to blame (but then only 1 pickup was affected...), did I knock lose a joint, or what? Is there anything I can do to test (without a voltmeter), or any suggestions? It totally sucks because I have this clean, well set up guitar but it isn't completely functional anymore. Thanks for any input!
loose wire. open it up and make sure you did not shake something up when you cleaned. Good luck

Did you get the pickup wet? I doubt it but it could be a short, but then it would clear itself up...

If you have split coil p'ups you could have knocked one of the wires loose.

Just check the wires.
First of all; never, ever, use WD40 on electronics.

The WD40 may be causing a short or you may have knocked a wire looose somewhere.
If you broke one of the little copper wires that wrap around the pickup bobbin, you're pretty much screwed and you'll need to replace the pickup.
Ok thanks guys I'm going to take it apart again and check the wire at the pup's side.
The humbuckers seem to be stuck to this metal plate that the screws for the height adjustment go through, so I can't really check that connection. How should I go about checking this?
DId you clean off the wax?
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No, how do I do that? Is that whats keeping it stuck to the plate cuz it seems pretty stuck.
It's not supposed to come off the plate! Look at where the wires come off the pickups. You should see where they are soldered on to the plate. Look for the tiny little copper wires soldered there leading to the pickup bobbin. If all of those little wires are intact, the pickup should be ok, but it's good to have and learn how to use a multimeter.