My 1993 Subaru loyale surges and gets poor mileage

hmm.. does it surge when you're stopped and idling? while driving? Both / neither? Is there a vacuum leak (check hoses to the throttle body and intake piping)? I was thinking Idle air control (if it has it) but when they go bad, they either stick shut and stall or stick open and rev to about 1500-2000+ and then back to idle (and repeat) at a stop anyway. You might look for a loyale forum and ask around there. Do you have an engine light on? If so, there could be a way to check the code (flashes?) and then look up the code, etc.

Mine had a similar issue, after I replaced those things it still misbehaved. I took it in and they replaced the solenoid that goes to the fuel injectors. Which sounds vague, but that's what he said.