I'm a first timer to VW's, love mine so far but having problems. It's a 2000 Jetta GLS 2.0L mk4 with 180k. I'm chasing the P0411 code, my pump is good so I'm trying to replace the combi valve and solenoid, bought these two parts at RockAuto. Solenoid was no sweat, Combi valve is giving me fits. I can only find two bolts that I think are holding it in and I removed those, left side was 5mm hex and the right side was 6mm hex (I thought it odd, a 5mm and a 6mm longer bolt). Still won't budge! Feels like there's another bolt holding it. With a mirror I can see other 6mm bolts that are further away from the valve and look like they hold the exhaust manifold on. I have no more hair to pull out! Please help!

 

I found the answer, you have to remove the intake manifold and the exhaust manifold heat shield with the combi valve attached to it. Kind a pain but not too bad.