I replaced the 02 sensor 3 or 4 months ago with a denso I thought I fixd the plenum well apparently I didnt. I know this is a general ? but should I replace the sensor just to be could it be fouled that quick. Btw cat is gutted

 

You could try cleaning it first...... getting any O2 codes?

 

No code but I wasnt b4 and it was nasty with the plenum leak and a clogged cat

 

Well, they aren't hideously expensive. Fix the plenum (again...), and replace it.

 

Well I started digging a little deeper and had a brain fart. Thinking blow by well the vent tube on the vc has a breather filter on it now so the only thing left is pcv so ordered a new one from dodge and went to autoparts house and got a glass fuel filter removed the filter element put it in line of the vac and the pcv the 1 mile drive back to the shop it had oil not alot but oil in it so im am gonna put a catch can in it and see if that helps. I really need to put the truck on a vac guage to check if intake pan gasket is bad.I just cant find the diy on how to do it ill keep looking though..

 

I replaced the plenum in my truck 30k miles ago. I have a little oil in the intake, in the back. I doubt its enough to half fill a teaspoon. I burn a quart of oil every 3k (same as before plenum repair). Truck has 180k. I'm assuming the oil seen in mine is blow-by (new dealer PCV at or around time of plenum repair). Truck gets 13 mpg's, no smoke. So anyway, are you sure the plenum gasket is even bad? If you see oil in the glass fuel filter dealio already, maybe that's where the oil is coming from (blow-by/PCV). Now if you've got a friggin half a quart of oil in the intake...yeah, do the gasket again.

 

1-2 teaspoons in back left corner im noticing smoke when i sit idleing for a minute or 2 just a puff of blue

 

Probably valve seals for your puff...... easy to change, just tedious.

 

seafoam works to clean things up... including o2 sensors..at least it has for me...I also used carb cleaner directly on the sensor and let it dry before testing with good results before.... I poured the seafoam directly into the intake VERY slowly with the engine running and I'm careful not to stall it....this way I cleaned out any oil on the plenum plate and was able to check it again after replacing my pvc valve to see if it was still an issue...
Sometimes it can help clean up the valve seals sometimes it doesnt do anything for the blue puff at startup... some say the carbon can actually help seal them... I'm not a huge fan of relying on buildup to seal things...

 

Hey You... On the puff of smoke it comes and goes thats what leading me to think its sucking oil from the intake into the cylinder i may be way off on this but its worth a try to fix b4 breaking into the heads again...

Auggiedoggy...Those are my plans for the weekend clean o2s put catch can on just to see already have new mopar pcv and seafoam the intake fix exhaust leaks (cheap headers) and see how she goes...