Volkswagen: Hard starting fuel injected 78 Transporter, starter fluid, warm weather

Question
Hi, I have checked all vacuum hoses, electrical connections,and replaced a small L shaped rubber boot on top the intake manifold. Yet in warm weather or cold, I have to shoot a shot of starter fluid into the breather to get the engine to start. Once it starts, it restarts perfectly. Plugs and points are new. Any suggestions?

Answer
Check the cold start injector, also known as "the fifth injector", which operates only when cold starting.  The Thermo Time switch, which controls the cold start valve, may not be working.  Also the cold start injector may be clogged (rust in gas tank can cause this).  Finally the double relay may be faulty, pin 86 supplies the voltage required for this circuit.