Hi,
First time posting but I'm hoping you guys can help. I've got a 96 Impreza Outback with the EJ22 and 90,000 miles (an old grandma car). The car will seemingly start and run fine for a while but will start to sputter, lose power and eventually stall. I have to then have the car sit for about 5-10 minutes before I'm able to get it running again. The difficult thing about this is that it is fairly random. Yesterday I drove 10 miles without issue. Got in the car again and made it about 300 yards before it stalled on me (fortunately I was able to make it to a parking lot). After about 5 minutes I started it back up and it was fine the rest of the day, another 40 miles.
I live in the city so it doesn't see much highway mileage. Given the randomness I don't like the idea of driving down a highway with no shoulder. The dash lights do not light during the sputtering.
Things I've replaced:
-fuel filter
-fuel pump
-valve cover gasket (this definitely seemed to be leaking as one of the covers had oil all over it)
-plugs (wires and plugs also were replaced about a year ago)
I've already tried taking it to a mechanic but of course it was running fine for him and not exhibiting any symptoms. I next tried a dealership but they said it'd be about $500 just to diagnose/look into it because it's so hard to reproduce. I'm kind of running out of options. I really don't know how to troubleshoot cars too well.
Any ideas on where to look next? How can I determine if this is an electrical/ignition issue vs fuel system, etc?
Thanks!