P0306 CODE ALSO. TRUCK WON'T STAY ON. on 2002 Ford Explorer

We have a 2002 Explorer v8 4.6L and it was working fine until it just didn't want to start and stay on about a month ago. We got te Misfire code and changed all spark plugs along with coils and booth on the 6th cylinder. Car worked for about a week and now has the same issue... What can it be? It trns on but only stays on i you keep your foot on the gas. Please help! Have tried everything

Asked by for the 2002 Ford Explorer
2 answers
Look at your last sentence..."IT ONLY STAYS ON IF YOU KEEP YOUR FOOT ON THE GAS". Was it like that before you replaced all those parts for a single cylinder (#6) misfire?IF it wasn't then I'd suggest working backwards to find a vacuum hose off or a mass air flow sensor unplugged THEN if your still getting only P0306 then stick to diagnosing what's related to that cylinder Give me more input I give you more output..... IF I'm even getting you on the right track.I can help with some suggestions for things to check without a scan-tool if that helps.
Hi This is Green's Garage answering. If you have replace the coils and spark plugs, then it may be a vacuum leak, a broken vaccum hose. We have a smoking machine to check for vacuum leaks.
Also you should check compression