Volkswagen Repair: running rough, golf cabrio, o ring

Question
Hi there. I have a mk golf cabrio, 1982 running a 1986 1.8l 8v with CIS , hyd lifters  and engine # starts with *GX...*
Problem is that it is missing on cylinder #1 from time to time. When starting from cold it starts ok then within seconds, starts to miss but after a waiting awhile seems to catch again. There seems to be no solid pattern to lead me to one particular cause.
I did replace the ignition leads and seemed to fix the problem for a while but shortly after it was back.
Maybe it's an injector but have not been too keen to remove the injector because of the difficulty of getting a spanner there to loosen the thing.(waiting to pull out the motor b4 I do this sort of thing)
Any hints or ideas really appreciated Jonn

Answer
Jonn,

You should check the C0 mixture first. The car may begin to run lean after the fifth injector shuts off and a slight increase in the C0 may fix the rough running.

Also pour some water down the back of the engine when it's running, if the engine sputters your injector seals are leaking and need replacing.  The injectors are only held in with the o-ring. Connect a visegrip plier to the fitting that you had your wrench on, and pry gently up under the plier.  This should release the injector.  Cut off the old o-ring with sidecutters (the o-ring will shatter if it's old), lubricate the injector and slide on the new lubricated o-ring.  Insert the injector back into the head and gently tap them until the o-ring grabs hold.

Good luck,

Paul