i have a 03 sunfire with DOHC has about 98,000 miles on it and it has started running really bad i changed plugs and coil and still running like crap this just happened overnight i have no clue anybody have any ideas Thanks in advance

Has it thrown any codes? What are the symptoms? Your profile isn't filled out do you have an auto or manual?

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<<<<<2003 Sunfire Sedan>>>>>

I'm a bit confused, what do you mean by changing the coil on an ecotec? Do you mean the module, little box on top of the motor secured by a couple screws?
I dunno, anyways- there are other areas at that milage to be considered, one is the fuel filter.
Have the fuel pressure tested at the fuel rail, if its below 50psi, the fuel system is the prob, the filter is the cheapest and easiest, and if you need a fuel pump, you'll get one anyways. Take it to a dealer, their scanners can monitor misfires and injectors in real time.

i got it figured out it was the ignition control module and i had local parts store hook scan tool up to it and all it was saying was mutiple misfires unknown problem so that helped out alot so just started changing parts and after i put module on cleared everything up