I have my 1985 vanagon and love it,only lately have this mystery problem and hope someone here will know.The van started acting like it doesn't have fuel,or a spark in higher speed and was bucking.Bucking consisted of loosing power and speed rapidly and a moment later regaining,a few km later the same.I have had en ignition coil replaced, spark plugs, distributor cap,fuel filter,spark plug cables and it is exactly the same.Only after each repair it does not do it right away.Also if it doesn't start on a first try,I have to floor my gas pedal and extend the starting time for over 10 sec.Then it starts.These two problems are haunting me.Please,can anyone help?

 

What kind of fuel injection system do you have?
Like are you running rich? Black tail pipe, black smoke
coming out, etc.

just off my head, are you using champion spark plugs?

 

thank you for your reply,I do not have smoke,or discoloration on my exhaust pipe.My spark plugs were changed a week ago,but I am not sure what the mechanic put in,will check first thing tomorrow together with the fuel inj.system.Do you think that spark plugs could make such a bumpy ride?My van has taken me from Vancouver island Canada all the way to Mexico and back this past winter,I had no problems all through the heat,climate change and elevation.

 

It depends, did this start after the mechanic replaced them?

Even something as dumb as a ground in the ignition can throw
the whole system off and cause such symptoms. It could even
be something like your fuel pump, on higher fuel demands...
when was the last time it has been changed? You basically have
to go through the whole ignition and fuel system step by step
for problems like this. All i've heard with spark plugs is do not
use Champion, in VW's they seem not to agree, all others seem
to be fine.