1998 Blazer 4wd 4 dr
l just had my lower intake manifold gasket and my evap canister solenoid replaced at the shop. Now there is grey smoke coming out from the oil dipstick when I pull it out. Anyone know why?

 

What did the oil look like? Is it possible some coolant got into the oil and is boiling off?

 

PCV not working

 

The oil looks good to me. If the PCV is not working would the check engine light be on?

 

Only if/when it detects a problem. Steam in the crankcase is released by the pcv valve, which is what you're seeing through the dipstick tube, which is connected to the crankcase, indicating a faulty pcv valve. Easy way to diagnose, pop the oil fill top off and look for excessive chocolate milk-like goo on it and the valve cover.

 

Purpose of the PCV is positive crankcase ventilation where blow-by getting past the rings is sucked into the intake and takes a second pass through the engine, instead of venting to the atmosphere (or leaking out the dip stick tube). If you have actual steam in your crankcase, then you have a much bigger problem.

If you have a big vacuum leak preventing proper PCV operation that could give you a lean O2 sensor code. Take it back to the shop and let them fix their screw-up.