Strange boost issue

Hey guys,

Noticed a weird issue with my boost this morning. I've been running a dawes/needle setup set to 20 psi now for almost a year without any problems. This morning I noticed my boost gauge only running out to 15-16 psi and then while under load at times I would apparently lose all boost (according to the gauge). I have checked all of my hoses and can't find cracks anywhere. The Dawes and needle valves are still set exactly how they always have been. The only thing I could think of is that the connection directly behind the gauge may be loose, but if that was the case, surely it should happen all the time? Could there be an issue with the turbo?

Any help appreciated.

Cheers,

Matt

check and/or re fit all the hoses. No idea what you drive but is your IC oily at all.
Forum needs as much info as possible

Mate if you are loosing all boost on the gauge but its still driving OK it's got to be the gauge. What about EGT's? If the boost really is all over the place the performance and EGT's would be all over the place too, maybe even engine lights and limp mode wouldn't it?

Maybe something is up... I mean if it's only getting 15-16 instead of 20, it's high end boost difference of 4psi, so you may not be noticing much performance difference . Just throwing it up there.

Also if its loose at the gauge the needle may flutter and also make a noise

what year and motor is it???

Seems to be a boost leak to me. If it is, the issue will worsen over time as the hole gets bigger. Check the underside of the intercooler for oil wet spots. This is a tell tale sign of a leaking intercooler. Check all your hoses and clamps too while your there.

Cheers for all of the responses. EGT's are still fine 200-300 oC most of the time. 2013 GU series 9. Haven't checked the underside of the IC, i'll do that next. The strange thing is that sometimes it is fine, other times it will appear to hold boost and then the gauge drops back to 0, even though it's still under load.

What brand gauge do you have? Is it a capillary type with a hose running into the cab? Or does it use an electrical sender?

Autometer ultra lites. Hose running into the cab.

Hmm i would be checking the hose going from the motor to the gauge aswell.