HELP: Engine Misfire on a 2002 Accord Coupe V6

Recently my check engine light came on. Thinking it might just be a bad
gas I got from this new gas station that recently opened up right around my
block, I drove the car till it almost ran out of gas and filled it up with
high octane gas and a fuel injector cleaner. It didn't actually work. Now my
car check engine light stays on. When you first start the car the engine
light flashes, TCS light comes on and the engine runs pretty rough, it
almost seems like its being flooded. So I brought the vehicle to Honda and
was told there was multiple misfire on all the cylinder. According to their
"manuals" its the EGR thats causing the problem and so they replaced it. I
picked up the car that same day and ran pretty good. Yesterday I took it to
work and ran great. After I got off the engine light came on and TCS light.
Droved it to honda later that afternoon diagnosed it and came up with
Misfire on cylinder 1 and low voltage problem. Unfortunately it was pretty
late when I took my car to the dealership so all they could do is read the
engine code and reset it. The service advisor was telling me it could be the
injectors and to have it clean or service its going to cost around
300ish+CDN.
Today is a different story. Started the car around noon and the engine
again runs like its being flooded, engine light flashing and TCS on. Any
suggestions what might be the problem?? During the time the car was at the
dealership I asked them if the spark plugs are still okay and they said yes
and told me still good till 140k km. The car sits at 93000km.
Any help or input will be greatly appreciated. I'll be taking the car again
tom afternoon [monday] to the dealership.

Thanks

Jessie