Volkswagen Repair: Idle Problems 1989 Cabriolet, volkswagen cabriolet, fuel mixture

Question
Hello,
I have a 1989 VOLKSWAGEN CABRIOLET L4 1.8L, 144k miles on it. I love the car but it is having trouble during idle (starting, stop signs etc.).  I replaced the distributor cap, rotor, spark plugs, plug wires, fuel filter, air filter.  I am wondering what is next?  To start it, I have to hit the gas to keep it at 1000rpm.  If I take my foot off, it either dies or sputtters and dies.  After warm up, it is the same or worse.  I think I also may have an exhaust leak (hiccuping, and popping at the exhaust pipe).  Would that make a difference?  I am going to adjust the idle screw out, but I will have to take almost all the way out.  Any suggestions would be greatly appreciated!!

Answer
I was thinking fuel prooblem as I was reading and when I got to the point where you said the exhaust is hiccupping and popping -yes the fuel mixture is wrong.   Turn the screw back in not out.  While I havn't done fuel injection, I am thinking that procedures must be the same as for a carb.  -- turn screw all the way in until it lightly seats itself at the bottom...then turn out 2 1/2 rotations(maybe 3 1/2 but try 2 1/2 first)  Now while you are in the engine compartment with the motor running, hit the gas and rev it up quickly and let go of the gas....is it popping?  If so, go in 1/4 turn and rev it again to see.  Your trying to eliminate the popping.  Once that is gone------your there with the mixture, you may need to adjust the idle speed and leave it.   Let me know..but do leave in the initial problem for I do not remember names.  Thanks