Hello, I have a 1991 F250 with a 7.3L IDI. Aftermarket ATS 088 Turbo. Truck blows a profuse amount of blue smoke on cold startup and once warm. Noticed a large amount of oil buildup in the air cleaner area and looks to be coming from the CDR Valve port. Could it be just my CDR valve or should I be looking into other items? Truck fires up first try and idles smoothly. Just lots of smoke. Need some ideas or help thanks.

 

Retarded timing.
Your IP/injectors have worn to the point that your timing is signifigantly retarded; advancing it will both remove the smoke and increase your power level.

IDIs burn oil vapor cleanly; you can be sucking a ton of engine oil into the intake and not have *any* smoke. Smoke is fuel related - white is unburned, blue is partially burned/retarded and black is overfueled(aka not enough air).