You absolutely have to run a PCV system.
Ok, so I suppose you probably could get away without it, but you really should run one. If just for the healthy long life of the engine if nothing else.
Engines like this need to meter all the air that comes and goes from inside the engine. So your PCV valve (in the valve cover on a 351 I think?) should go to full manifold vacuum and the return air should be plumbed into the air intake, in front of the throttle body, but behind the air filter so it gets clean air.
So this is an SD engine, rather than MAF then? I forget, but if it's MAF, then the inlet for the crankcase should be behind the MAF so it can read everything that comes into the engine.
The MAP sensor on these engines is hooked to vacuum, correct? If so, is yours full vacuum from the intake manifold and not just an air port in front of the TB? If so, that should be good then. I would wait until after you install a functioning PCV system before you change the MAP sensor. They do go bad of course (like anything else), but it's pretty rare in my limited experience.
If you're equipped with a BAP sensor though, it does not get plumbed to vacuum.
You may already be aware, but if the sensor has the little plastic thingy on the end of the tube, then it's a BAP sensor and it does NOT get a vacuum hose. If it does not have the thingy, then it's a MAP sensor and it gets plumbed to vacuum.
Just makin' sure here. They're identical in look and function except for the nipple thingy and how the ECU interprets the signal.
For the tank, I'm thinking it should be OK. I would use a vented cap from an earlier application though, since you do want air to be allowed into the system.
You are running a return line to the rear though, correct?
Paul
