Manual boost controller - irritating issue

[dss15]

Hey All,

Recently pulled my dual stage BC out and put in a simpler MBC, don't need two stages of boost for my daily driver. Thought I'd "keep it simple".

The challenge - the MBC seems to 'reset' every time I turn the car off. I do the stop, starting and fiddling to get it to boost and hold properly at .9bar at all ranges of revs (decent BC, no spikes!). I turn the car off, and the next time I go for it it pulls perhaps .7max unless I rev the guts out of it, at which stage it jumps to .9-1ish.

No leaks, I replaced all the clamps recently, everythings tight, vacuum hoses even have baby clamps.. its pissing me off. It's an MBC, so as far as I know it should work exactly the same each time?

Frustrating the hell out of me. Any ideas?

 

[tmus]

maybe something is getting stuck inside?

 

[_Wing_]

Are you sure there are no leaks because even if you tightened everything and looked everywhere things are different when the car gets going, so try to pressurise the system to test for leaks.

Also, is this happening under different conditions? Say you set it up last night when it was cold, then drove it the next day when it was hot?

 

[dss15]

I haven't done a proper pressure test but the boost levels don't fluctuate when I plant it.. usually when there's a leak it'll peak and drop pretty quickly. It seems to hold steady! Tried it during the day a couple of times and last night a couple of times. I'm going to just go back through all the hoses and see if I did miss anything...

And tmus that's something I hadn't thought of, they do have a pinhole side to them.