My classic has a boost spike problem, at WOT it boosts to 1.2 bar then pulls back to 0.6 and fluctuates between the 2. I have replaced the solenoid, all the pipes for silicone, just fitted a vf28 but it did the same thing on my td04. Have tried a pipe from turbo to actuator direct and it holds 0.5 bar rock solid so the actuator seems fine. There is a restrictor in the line nearest the turbo so not sure what else could cause this. Want to get it controlling boost properly so I can take it for a remap

 

Drilled the pill out slightly and problem solved

 

Does it have a decat ?

 

Most likely

 

My classic has the same problem and im pretty much standard, sorry for being a tit but whats the pill?

 

First thing you need to do is connect the plugs under the dash and with the ignition on but car not running, the solenoid should be clicking, you need to clean it by spraying brake cleaner through the lines, give it a good soaking. This will probably solve your issue if your car is standard.

The pill is a small brass restrictor in one of those lines close to the turbo