My truck sputters / studders / surges - whatever the terminology - it doesn't run smooth just off idle...

It idles smooth, and at any rpm above 1800, it runs smooth. It happens when I'm just cruising, doesn't matter which gear or speed. When I'm going down the highway at normal speed or going through town just cruising, and press the gas ever so slightly, it studders. If I accelerate hard, it studders jast at first then it opens up and runs good.

I've changed all plugs, coils, boots, fuel filter, air filter, cleaned the MAS no program codes come up.

I have a 5.4L 4x4 2001 F150 with an edge programmer, flowmaster exhaust and a cold air K&N intake kit. There is no loss of power, that I realize.

I'm at a total loss! Please help!!!

Thank you in advance for your help!!!

 

What plugss did you use? Modulars are very picky about the plugs they like. How about a fuel pressure test? Might wanta do one of those.

 

Hi, thanks for your reply. I used the stock replacement motorcraft plugs.

 

What happens if you return the Edge to stock?

 

Nothing changes - it's the same.