Tuning Impact fast leak at back of Plenum

Anyone know the fix? Thanks in advance!!!

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Take the reg gauge off, then the plate below it (4 screws) then you'll see a big 5mm hex head screw. Unscrew that then slide the block off the valve house.(towards pictures left). You can inspect the orings on the outside of the valve house. It's most likely one of those.

If not its probably the one on that end of the plenum. Either way you gotta go just a bit deeper.
 
Thanks! Looked at those and they looked ok. To my surprise, ther wasn’t a boring at the end of the plenum. I’ll try and replace the three on the valve housing and see what happens.

Yeah the one I was referring to on the "left side of the plenum" is actually attached to the valve house. Replace all three and be careful as you insert the valve house into the block with silicone grease and I bet thatll take care of it. 👍