I have a 98 version 4 sti.

I have recently bought a new coil pack, leads (performanceleads.co.uk) new standard air filter, new plugs (NGK 7's) and a full oil change.

I have also had a new radiator and a h&s decat pipe fitted.

Now i have problems excelarating. At low revs it is fine but then it seems to come in and out of boost. It's worse on the motorway at say 3000 revs and then you put your foot down. It seems to judder.

I previously put a thread on but i'm not sure where it ended up. I've tried to put it on the tech forum but can't work out how to do it.

Is this possibly a boost solenoid proble. Someone has very kidly replied to the last thread and suggested it might be.

The car has covered 60,000 miles.

Any thoughts would be much appreciated.

Mark