Sputtering Subaru!

I have a 2000 Subaru Impreza that has 185,000miles. A while back, when it was first started while raining it was sputter and almost stall and the check engine light would come on. My mechanic did a tune up and the problem stopped until this month when it started doing it again. It does this only during a very rainy period. It I warm the car up for about 10 minutes before driving away, all is well. Any ideas?

Your spark plugs wires are looong overdue for replacement, so if your mechanic did not do this when he performed the “tune-up” (whatever that might have consisted of), then I would suspect the plug wires as the likely source of the problem. If your car has a distributor (I don’t think that it does), then a cracked distributor cap would also produce this symptom during very damp periods.

You are not clear about whether the CEL is lit up again. If it is, then the problem is probably more extensive than what I suggested above. If the CEL is lit up, accurate diagnosis begins with scanning the car’s OBD II system for stored trouble codes.

Mecdhanic did replace the wires when he did the tune up about 2 years ago. He also suspected the wires which is why he changed them. Check engine light is not on now, but when it comes on it stays on for 3 days then goes out.

When the CEL first comes back on, drive to an auto parts store to have the codes read. Most Auto Zone and Advance Auto locations will do this, gratis, as will some NAPA retailers.

There is a great deal of quality difference in spark plug wires. Those supplied with new cars hold up pretty well. Some aftermarket wires are equal to or better than the originals, but most are not.

It is very possible the new wires 2 years ago are now sensitive to moisture. You can clean them with alcohol or a solvent cleaner and see if it helps. New wires are pretty simple to buy and install yourself. I’d replace the wires and see if it helps.

Ok great guys, thanks for the help. I am on the way to Autozone now!