Juddering when accelerating hard
 

I've been having probs with my 99WRX especially when starting from cold, the car struggles to pull away especially on a hill. Once the car has warmed up all seems fine if it is driven easy but try accelerating on an incline on a motorway or try some quick acceleration and it feels like it's missing. I've had the coil pack, plug leads, lambda and plugs replaced (all subaru parts) there are no faults indicated by the ecu (reset recently) the car cuts out when the MAF is disconnected so I'm running out of ideas. I did read in another thread something simillar where a post suggested a fuel problem. I'm not particularly mechanicaly minded but it did seem reasonable that there might not be enough enough fuel getting to the engine when it has to work harder.
Anyone got any thoughts on this and where should I start looking?

Had the problem and solved it, but not the motorway prob you are having. Mine was residue on the clutch plate which causes the juddering from cold, hense why you don't experience it when the engine is warm.

2 option to fix it:

1, If your car is under warrenty Subaru will resolve the problem for you

2, A couple of launch start around 4500/5000rpm and that solves it.

I hope that this is of some help, you could also take it to Subaru to fix it if it is not under warrenty but I was told it NOT CHEAP.

Adzi