Hi Guys, The Same Old Story...engine Sputters And Misfires At Low Rpm...idle...starts With No Problem...code P0303 Which Is Misfire Cylinder #3...replaced Plug, Wires, Cap, Rotor And Coil....no Change...65000 Miles ...short Trips....

If you have a noid light, check to see if the injector is receiving a pulse. If it is, you could replace the injector or swap it with a different one and see if the misfire goes with the injector from cylinder 3 to the other you swap it with. If it does, buy a new injector and replace it.

If you have a noid light, check to see if the injector is receiving a pulse. If it is, you could replace the injector or swap it with a different one and see if the misfire goes with the injector from cylinder 3 to the other you swap it with. If it does, buy a new injector and replace it.
You mean that there are 6 injectors in my 4.3 V6 W motor?...like multi port??

Yes, you will have to replace the #3 injector with this.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=7942446620&category=33557