Hey hey I just bought a 99 ram van 3500 with the 5.9 in it. Guy I bought it from couldn't get it running right and I wanted a van and it was cheap so here we are now it's my problem lol.

Previous owner let van sit for a year. Tried to get it going idles good but looses power, bogs down, and tries to stall out if you give it gas in gear. He has already replaced lots of gaskets, injectors, distributor cap, wires, plugs, and a few sensors.

It also sucks air through the oil cap and oil dipstick. Is NOT blowing oil out or anything just sucking air.

I had a feeling it might be a clogged cat, as it was throwing o2 sensor codes with brand new sensors but won't know for sure till tomorrow when the relatively newer cat goes on. (I'm not the one replacing it so I don't know if it's actually clogged or not, I'll just know if it fixes it. I'll be trailering the van home on saturday)

 

Clogged cat wouldn't surprise me, blown plenum sounds like a certainty..... (which leads to a clogged cat....) Pull the air filter housing, crack the throttle wide open, and have a look down there. See oil? Yep, plenum is blown. Gotta pull the intake to fix it.

 

You have to remove the intake and repair the gasket for the plate under the intake manifold. Any leak in the gasket causes vacuum to be pulled in the crankcase.

This video show what I'm talking about.