Subaru Repair: After rain: check engine flashes, uneven acceleration, xs 5, cylinder misfire

Question
Vehicle: 05 forester XS, 5 speed, 34K miles

If it rains overnight, on some mornings I get a flashing check engine light. The car will not accelerate evenly and engine vibrates intensively while idling.

Problem goes away after 15 mines of driving so the dealership cannot find any codes in the computer. Any ideas?

Thanks,
Aleks

Answer
The dealer cant find any codes or they don't know what is wrong?If the light is FLASHING the ECM (engine control module)is seeing a cylinder misfire which coincides with your complaint of rough running.The vehicle is very fixable, I would be more persistent with the service advisor.Inquire to what code has been set and what they have done to attempt a diagnoses.Explain to the service department that it is there responsibility to OUR ENVIRONMENT to get your car running properly.Whenever the check engine light comes on the ECM is trying to tell you that your vehicle may be excessively polluting our air .You are doing the right thing by taking it in ,but it always annoys me that the dealer wont give it the time it deserves to properly diagnose and repair it.Please keep at it and i know eventually a result will be had.

Justin
All Wheel Drive Auto