LeMans

I acquired a 94 WRX some 5 months ago and the engine sounded fine.

Now upon start up with the automatic choke on, as this cuts out and goes onto idle as the revs come down to c2,000rpm there is a ticking noise that sounds like tappets (or a chain if it had one!).
If you rev the engine you hear this tappety noise as the revs drop again (but not when the revs are rising)and this is in the region of 2,000-2,500 rpm and then it disappears again. As the engine gets warmer the noise is still there but not as noticeable.

I do not recall the noise when I first acquired the car - recently I have changed the plugs, cambelt and oil but cannot imagine it is any of these that have made a difference.

Perhaps this is just a typical noise that an Impreza makes but does anyone have any ideas?.

Spoon

I witnessed this last week at a dealer friends when a chap come to buy a 94 WRX.

On start up it ticked (tappets), it ran fine and once they returned from a test drive it had disappeared.
They at first put it down to standing for sale for a while but later that day after the guy had agreed to buy it they checked the oil pressure before handing it over.
They found it to be lower than it should.
What they did next I'm not entirely sure but they mentioned something about oil pump shims, some come with 2, others with 1, this car had none.
I know they didn't replace the oil pump but whatever they did it lifted the oil pressure and cured the ticking.

They also mentioned it would have cost £140 had it been a customers car.

Perhaps somebody here can shed more light.

LeMans

Makes we wonder whether the oil I am using now differs to that before.

Don't know what they would have used in Japan but I used Magnatec which I haven't heard of any problems with.