I have an older and well-loved 2003 Subaru Forester, manual transmission, about 180,000 miles. I bought the car used about 2 years ago. Since then, I have had extensive work done on the car, which is maybe to be expected for an older, getting-up-there-in-mileage car. In the past two years I’ve had the brakes done, head gasket replacement, new clutch, new exhaust manifold, and new catalytic converter.
A few days ago, I got up early to go to the gym before work. Car started fine, drove the short distance to/from the gym, and then about 45 minutes later went out to drive to work. When I started my car this time, the engine started rough, sounded loud/rumbly, the car was shaking, and the check engine light was blinking. The check engine light is usually always on (it comes back an evap code), but it has never blinked before. I turned it off, waited a few minutes, started it again, and the same thing happened. I left my car, got a ride to work, and called my mechanic and explained what was going on. We had gotten a heavy, wet snow the night before and he suggested it was probably the spark plug wires and that I let it dry out and then drive it into the shop tomorrow. I figured this made sense, especially because my car was parked in a closed garage overnight so it didn’t get snowed on, but then sat outside in the snow/wet while I was in the gym and then I parked outside again before leaving for work. I got home and the car started and ran fine and dropped it off at the mechanic’s the next day.
When I went to pick it up, he said that there were no misfire codes from the check engine light, only the evap code, and that he sprayed down the spark plugs and wires in the engine and didn’t get a misfire or see anything out of the ordinary so he said to just drive it and it should be okay, but if it happens again I may have a coil problem. I drive 45 minutes to/from work every day as well as out of town pretty regularly, so “waiting to see what happens” isn’t an ideal fix for me as I don’t want to be broken down on the side of the road, and my experience has been when things go wrong with my car they will definitely go wrong again-it’s not like getting a cold where it just goes away on it’s own! I like and trust my mechanic and he’s familiar with Subarus and does good work. I trust his diagnostic abilities but would also like a second opinion if any of y’all have any insight! Thanks!