Boost Fluctuation Question.

Alright folks,
Got a quick question on a boost fluctuation issue that I am having at the minute.

Had the car up the A68 yesterday and noticed at mid-range my boost guage needle is fluctuating between 1 and 1.4bar.
If I floor it the boost holds steady at the 1.15bar that it is set to on the HDi Boost Controller.

Fluctuation only seems to occur when I am lightly accelerating and is very noticeable as you can hear the car sort of boosting and holding back as the boost needle bounces around.

Has anyone heard of this before?

Have checked all of the vaccuum hoses and all are okay.

what dump valve do you have fitted?

Hi Jonny,
Currently has a Forge Recirc fitted but soon to change to your old Hawkeye topmount with no DV courtesy of Colmoo.

Sounds like the spring in the DV is too weak mate.

Cheers Jonny,
Will fit the standard one tomorrow and check it again.

I have a full selection of forge springs (all 4) here if you want to try a stronger one

Thanks Jonny,
Took recirc valve apart, cleaned out and stretched the spring and all working great now,
didn't realise that it must have been venting off for a while as boosts totally different now.

Thanks.