I have a 94 F-150 5.8 . There is a loud rattle coming from behin the engine, It sounds like a valve or a solinoid opening and closing very fast. Anyone have a idea what this could be and if it is something that could cause a problem.

 

cracked manifold or an exhaust leak some were doen the collector pipes

 

I will try to check for that tomorrow, but it sounds more like it is right behind the intake. And it realy rattles faster than any exaust leak I've ever heard.

 

It's probably your PCV valve rattling. That is what mine is.

 

This would be my first guess.

As already suggested, the PCV valve is a possibility too.

Good luck!

 

If it is te PVC valve does that mean it needs replaced or is this normal?

 

well mine doesnt rattle lol probable replace it

 

Actually....it should rattle. I've found the aftermarket one to be noisier but probably because all the junk that was clogging my original from 184,000 miles.

INSPECTION

• Shake positive crankcase ventilation valve and carefully inspect for splits or cracks.
• If positive crankcase ventilation valve does not rattle or is damaged, replace positive crankcase ventilation valve.