my 95 1.8 impreza ticks but it comes and goes I've been told it's the tappits or the oil pump ,I've been told that a better oil pump is available and should solve the problem any body eles suffered the same problem

 

Good chance that it could be the injectors, that is of course if it is fuel injected

[Edited by submannz - 4/17/2003 12:22:50 AM]

 

I guess by the year your engine has hydraulic valve lifters, in which case it's a good bet that one or more of them is losing oil pressure occasionally. Is it ok when you bring the revs.up? Not uncommon on engines with a few miles on them. The first attempt at a cure is to use a flushing agent (e.g.Wynns, STP etc., there is one that specifically mentions hydraulic lifters) then change oil and filter. Failing this, it's down to replacing the offending (preferably all) the lifters. Not cheap!
JohnD

 

try here - may give you a bit more info