Sparky and his 4 little friends
If your 1975 to 1980 VW Rabbit won't start, and you don't have spark,
Chances are your Points are dirty, and or maybe your Condenser is shot.
Below is a picture of the points distributer from my 1979 2Dr.
These old Points systems are Very simplistic, But tend to wear out quickly, and require more maintenance then
the newer Breakerless Ignition System.
So How to Test it? Well, remove the cap, and rotor, and dust cover if it has one, and look down into the mess.
The points open and close when the little cam on the distributer shaft comes around. Turn your engine over by
hand until the points are fully open.
Now get a flash light and take a good look at the contacts. Are they pitted, dirty, or do they looked burned?
If they are, or they are over 15k old. Replace them. Now if your in a pinch, you can take a small piece of
sandpaper, and put it between the two contacts. Then turn the engine until the points are fully closed, and pull
out the sandpaper. After 2 or three times, even the ugliest set of points should fire.

To Adjust the points, you will need a feeler gauge set. These are cheap, and depending on your year model can
be substituted by a match book cover.
Rotate your engine until the points are all the way open and measure the gap between the contacts. It should be
about .016 inch give or take a hair.
Thats all there is to it, your done.
1981 to 1984
The Breakerless Ignition System
This later system is much more reliable, but much more expensive to repair, and a little harder to test.
Now thats progress!
Basically Vw Replaced the Points with a "Hall Effect Sensor" This is located where the points used to
live, and costs about 40 times more to replace. Luckily it hardly ever fails. It counts the 4 gaps in a disk
that is attached to the distributer shaft. Every time it senses a gap, it sends a signal to "The Control Unit"
That in turn Sends the signal to the coil to fire.
The easy way to test a suspect system is to hook your test light to The terminals of your coil, and spin
them motor over with the starter. If the test lights blink, the hall unit is working, and so is the control unit.
I have never seen a control unit fail on a VW, but they do go bad on Volvo, so anything is possible.
If you need a hall unit. Order a whole distributer. Its only a few $$ more, and comes with a new cap and
rotor.
My Thoughts on Caps,Rotors,And Plugs

I Highly Recommend you get the Real Bosch Replacement parts
You can save about 12 bucks on Aftermarket stuff, but you will
most likely Hate yourself for doing it. Many of the crap-o-matic
Caps and rotor don't have good tolerances, and will cause all kinds
of no/hard start problems.
I Would also advise you to avoid the Bosch Platinum plugs.
There not really made for these older systems no matter what the
parts guys say.
Stick with the standard issue plug, and your bunny will thank you.