hey my 95 f-150 makes a werid repetitive noise while accelerating. I have been reading posts and i think it is what is known as piston slap? What is causing this and how can it be fixed? And if i am wrong about what piston slap really is... please update me and give me some insight upon my problem.

 

I'm going to say I think you may have spark knock or detonation if you only hear it accelerating, I would suggest you check the ignition timing.

 

I have it too, you can determin which piston by pulling plug wires untill it subsides. The only way to fix it is to replace the piston. Ive had the problem for a long time, it doesnt affect the way it runs its just anoying

 

Mine has some piston slap, too. But I agree, if you're hearing it on acceleration, it sounds more like spark knock.

 

yeah it is only during acceleration... and it seems to be louder when the truck is cold. You can almost feel the sound as it is happening.