This has the EHM - it's got a couple of photos on the Provent
http://www.lostjeeps.com/forum/phpBB3/viewtopic.php?f=98&t=22703basically the Closed Crankcase Ventilation system blows oil vapor out of the engine block and it's routed to the intake manifold - the Elephant Hose Mod - just vents it to atmosphere - the Provent puts a trap in the line to condense the oil out.
I put a Magnaflow 2 1/2" instead of stock - some folks have pulled the muffler out completely - anything that removes that restriction with improve turbo response.
The Tuners vary - I don't know that anyone has enough mileage to say for sure the reliability impact.
I'd be very cautious of any box that you plug into a line.
The ECU remaps from GDE and Inmotion are a better ideas - GDE sounds better but it costs more, and they're active participants on LOST.
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2005 CRD
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