Too much vacuum

[Oldsguy]

Changed oil filter/pcv housing due to failed diaphragm, but reused original hoses...this was after having turbo replaced at dealer ship. Now it seems there is too much vac, and when i remove oil fill cap to release pressure car runs rough. No codes as of yet..
What may be causing this issue?
Dealer says oil trap..can't find what or where that is on car??
TIA

[RickHaleParker]

Now it seems there is too much vac, and when i remove oil fill cap to release pressure

That statement is contradictive. It should have a vacuum but a positive pressure is not good. It cannot be both.

Positive Crankcase Ventilation means it ventilates the positive pressures from the crankcase not that the crankcase pressure should be positive.

Do the glove test and show us the results.

You might try cleaning the Banjo if you have positive pressure, ( bolt #12 & #17 below ). The Banjo plays the same role as a PCV valve. Clean it but don't modify it.

Oil trap is mounted on the front lower side of the block, #1.

[Oldsguy]

Not sure what glove test is, the pressure wants to pull oil fill cap back into hole.

[abscate]

Not sure what glove test is, the pressure wants to pull oil fill cap back into hole.

Okay, we call it vacuum when the engine is pulling in, and pressure when it blows out. Both are actually pressure differentials, of course. It’s normal and necessarily to have the engine pulling in through the filler cap

[Oldsguy]

Ok makes sense. Just want to make sure its ok to drive like this. So there should be vac noticed when removing cap.
Thank you

[RickHaleParker]

Not sure what glove test is, the pressure wants to pull oil fill cap back into hole.

Glove test:
1. Remove the filler cap.
2. Tye a latex glove over the filler spout.
3. Start the engine.
If the glove deflates ( Vacuum or Negative pressure relative to atmosphere pressure ) the test is a pass.
If the glove inflates ( Positive pressure relative to atmosphere pressure ) the test is a fail and the PCV system needs service.

[BlackBart]

So there should be vac noticed when removing cap.
Thank you

Yes.

[abscate]

There is a TSB on the actual measured crankcase vacuum, measured at the dipstick , of better than 0.2 kPa vacuum. This is to be used as a diagnostic for PCV evaluation, not a guide to cleaning.

[BlackBart]

Too much vacuum sucks.....