ok so here is what i got. i swapped a 02 impreza 2.5l into my 92 4wd loyale wagon. had a subaru tech intall the ecu and everything. The car runs and drives fine. but lately i have noticed a lagging and sometime shuttering of my engine upon acceleration. i have replaced the c.v. axels and front lower ball joints the driveline train is as tight as can be. but here is the wierd part. about a month into the swap my car was having a rough time starting somethimes taking two runs of the starter to finally start. when it does start though the idle bobbels up and down and even some times dies out. this is more evident when the car is cold started. when warmed up it doesnt have as hard of a time.

and even warm the cars idle will drop down to 400 rps or so.

 

so my assumption would be the fuel pump, or the fuel pressure regulator would be the culprit. i have tried replacing the fuel filter but with no luck.

 

so i am just curious if someone could give me some insight that has had some experince with the subaru loyale wagon or later gen. subarus ea82/s. thanx

 

and just out of curiosity where is the fuel pump and pressure regulator located on a 92 subaru loyale 4wd wagon exactly?

Was the check engine light and OBD-II port properly hooked up? What, if any, codes does it indicate?

 

Your problem sounds like a sensor issue - CTS, etc. It does not sound fuel pump related to me. The fuel pump is located on a shelf in front of the tank under the car. The pressure regulator is part of the EJ251 and located on the fuel rail after the last injector in the passenger side.

 

GD

agreed - what codes do you have?

 

hopefully you have codes and don't have to throw parts at it but:

were the plugs/wires replaced at all during the swap or are they original/unknown miles?

are they aftermarket or Subaru wires?

 

how long did it run great?

you gotta realize that the part that is not working is controlled by something else. suspect something else.