- Thread starter
- #21
Surf and Dune
Well-known member
- May 8, 2021
- 283
- 277
Replaced EGR valve and cooler on my 2007 Duramax. Check these pics out!
- Thread starter Surf and Dune
- Start date
Rockwood
Well-known member
- May 5, 2021
- 5,026
- 6,400
It's mainly the oil vapor combining with the diesel exhaust that cokes them up. This is what I dealt with on a MKIV VW TDI:
That's the intake manifold's plenum with only about 3/4" of breathing left... Gained 30hp (out of 90, lol) cleaning that out. Getting a oil separator helps. The EGR system prior to where the PCV attaches to the intake was free and clear of soot.
A tune in CA will likely land you in the "tampered" category (which may give you the added fun of annual smog inspections). You'll have to find someone still willing to roll the dice with the EPA (unlikely) and then completely remove the tuner and all tattletales prior to taking it in for smog.
That's the intake manifold's plenum with only about 3/4" of breathing left... Gained 30hp (out of 90, lol) cleaning that out. Getting a oil separator helps. The EGR system prior to where the PCV attaches to the intake was free and clear of soot.
A tune in CA will likely land you in the "tampered" category (which may give you the added fun of annual smog inspections). You'll have to find someone still willing to roll the dice with the EPA (unlikely) and then completely remove the tuner and all tattletales prior to taking it in for smog.
Last edited by a moderator:
