05-03-2012, 10:20 AM
tomw1123 Wrote:I have no idea i just bought a cheap [boost gauge] one on ebay lol
This could be your issue, my last HDi had a cheap ebay gauge and it was reading 21psi but actually only making 17.5psi so thats about 15% out no reason why it couldnt be your gauge being partly to blame.