I have a 2002 f350 v10 that has been misfiring at idle as soon as I give it gas it runs fine. It does not do it at every stop light or even every day it also does it at random times such as some days when it is cold other days when it is hot. The truck has all new ignition coils and spark plugs and IAC all motorcraft brand and all the pcv hoses have been replaced recently. I checked the crank and cam sensors they checked ok. Im leaning towards a fuel issue since the spark plugs showed signs of lean conditions. And there are no codes. Thank you all.

 

Measure the fuel pressure with a pressure gauge.

 

I have not had a chance to get the fuel pressure while it is misfiring but when it is not misfiring the fuel pressure is good. I was not thinking the fuel pump is bad since it does this sporadically and it gets better at high rpms. I guess another thing I should look at are gaskets.

 

You should probably do something like following an organized troubleshooting path instead of making random guesses.

 

Its not the fuel pump, there is plenty of pressure at the rail when misfiring. So now I am going to check the injectors.