Having a little problem with my Mustang:

2006 Mustang GT
28k miles
only owner

After my wife and I had our 2nd child, I took a month off work and the GT sat for a month outside and I did not even have time to go out and run it around the block. I rained heavily two times that I can remember and it was under a tree that has dropped it's fall leaves.

I finally went back to work. The car was very low on gas and as I pulled into the station, I noticed the CEL was on and steady. I thought it might be the gas cap issue again, so I filled it up and drove off to work.

While driving to work, I noticed the engine was running rough and the CEL started to flash. It would stop flashing and stay steady when I was at a full stop and start again while driving.

I took it to Autozone and the code said a misfire on #8 plug and something about the injector. I dumped in some Seafoam into the tank and just looked into the engine compartment. Looks like the area around the #8 plug was clean (washed off) of dust.

I am thinking:
Water from the rain on the #8 coil?
Bad #8 plug?
Injector problem?

suggestions to check... easiest to hardest?

 

Have you ever cleaned the Throttle Body??
Changed the Plugs?
Use a Oiled Filter? (CAI)?

 

Never cleaned the TB.
My Mustang has 28k miles, should I have changed them already?
Has a K&M filter

 

Cleaning the Throttle Body is the first thing to try. Many, MANY threads on how, what amd what not to do.
Using a "Oiled" filter, there is a possibility that the 'Mass Airflow Sensor" or MAF needs cleaning. Again, MANY threads on how to here.
The Plugs are a different tune. Also depending on when the '06 was built. If it's a early year build you will have the 2 piece plugs. "Pains in the ***", late year builds with different heads and different plugs. As far as should you have changed them, that is in the eye of the beholder. And a"TON" of threads on that excitement.

Happy Readin there bud........