Volkswagen Repair: 82 VW rabbit fuel injection, vw rabbit, running on three

Question
i have a 82 VW rabbit with ~175,000 miles on it here in houston, tx.  it has the bosch CIS injection system on it.  the car is only running on three cylinders right now.  i have replaced the distibutor and coil and verified spark on all cylinders.  it appears that one cylinder is not recieving fuel.  i cleaned the fuel injectors, but that didn't help.  would this be related to the fuel distribution block or the frequency valve or is there some other component i'm overlooking?

Answer
Harley,

You can remove the injectors without removing the fuel lines, put each one into a small jar and crank the engine.
Watch the spray pattern and the amount of fuel in each jar.
The fuel should be nicely atomized and the amount of fuel in each jar should be equal. If one injector is not spraying nicely or one jar has less fuel, replace that injector. If you look closely at the end of the injector, that was connected to the fuel line and see rust, the injector is no good.  

The fuel distributor won't stave one cylinder, it usually affects all four. Low compression will cause one cylinder to misfire as well.

Good luck,

Paul