my 04 gc has rough idea all the codes came up 135,300,303,305 just did new spark plugs was running great put gas in went for a drive and bam all this happen

 

Ah.....what?

 

I did the same thing almost. I changed the plugs, wires, distributor cap and rotor. It was fine for two days then check engine light. Codes 0300, 0305, anyway changed the coil and it cleared everything up!!
It might be worth checking it out..

 

We still don't know what engine he's got.