Power problems in 1999 TS-R wagon

[sub-r-u]

My wife has a 1999 TS-R wagon, it just dosent seem to have the power you would expect from a 2 lt engine, ever since we bought it it seems to be gutless on the hills, and when its warming up under acceleration it has a gentle surge felling, of acceleration then Plateau, acceleration then plateau........ as it gets up to speed.

It did have a fouled plug in number 4 , and has been looked at by subaru, but they didnt seem to see the problem, we have just put up with it. It dosent seem to affect over all running as we have done some big trips in it no problem, but sometimes you can feel it miss a bit, and wonder if its going to breakdown, but it never has.

It has been like this for two years now. Starting to really annoy me now, must be using more fuel like this.

Any Ideas???? Anyone had same problem?

I have heard that if the Cam is out a tooth it can affect power, but not sure if it surges, or misses also?

Have also been told coils, but you would think it would have shat itself by now?

[MercuryFree]

I'm told a faulty o/2 sensor can cause the "surging" like behaviour under warm up conditions, and mine (I don't even have the o/2 sensor installed...) sure does it

[kamineko]

yeah the TS-R engines should give you reasonable power.. they are the best of the 2.0L non-turbos

it could be any number of things, but personally i'd be checking the air filter.. checking cel codes and resetting the ecu.. checking the knock sensor as they can crack with age

another random thing that comes to mind is stuffed cat converter or muffler but you car sounds too new for that

spark plugs would be a good thing to inspect as their condition can indicate whats going on.. oh youve done that

potentially a leaky injector or dud throttle position sensor could cause surging

but yeah its all a shot in the dark on a forum. really need someone to go over the car in person

[Guest boostin]

Try resetting the ECU and "relocating" the knock sensor to a cable tie on a hose.

The cambelt tensioners are notorious for bouncing too, causing all sorts of issues.

[sub-r-u]

Is there anyone in Christchurch or Ashburton that is killer with sorting out subarus?

Dont mind if its a proper Subaru dealer, Id rather spend up to 1k on a great fix than spend a few K on a new car! What I dont want to do is spend several hundred on no fix like last time it went to a Southern Subaru Dunedin.

Also anyone know if likes of a 2002-2004 legacy motor will bolt in or is all the ecu/mounts different?