Rep Power: 0

My 2005 Civic Coup has about 70k km on it. I added one bottle of fuel injector cleaner when refueling last time. This isthe first time (the only time) I use fuel injector cleaner. By the end of that tank of fuel, the emission malfunction light came on. it went off once, but came back on again. today I can hear that the sound of the engine is a bit louder and it is harder to accelerate as well. Any ideas? Thanks.

 
Rep Power: 812

goto auto parts store and have them check the engine code. that will tell you whats wrong. generally its a bad idea to use fuel additives you can buy locally, they are all junk and many can cause problems.

 
Rep Power: 278

I think you mean the check engine light. If it is, I heard you can get your code checked at Parts Source.