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the 'bunny hop's probably you hitting the overboost ignition cut

get one of those cheap pneumatic boost controllers (or splurge on a big dollar elec one if you prefer)

cheers mate, ye im actaully gonna get a boost controller in a few weeks it was meant to be done on the day i got my fmic but they had to leave it another day.

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Uhhh ok I dont see how a boost controller will help with overboosting if you dont have one on there already...

Firstly, what sort of car? How much is it overboosting by? And did you change anything else or only the FMIC?

A boost controller wont help at all if you have no boost control currently (ie its just the wastegate), as a boost controller simply cant make the wastegate open at any lower pressure than where the spring opens.

A bleed valve quite literally 'bleeds' some of the pressure so the wastegate doesnt see it, theres no way of making the wastegate see *more* pressure so that it opens sooner and therefore runs lower boost.

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Uhhh ok I dont see how a boost controller will help with overboosting if you dont have one on there already...

Firstly, what sort of car? How much is it overboosting by? And did you change anything else or only the FMIC?

A boost controller wont help at all if you have no boost control currently (ie its just the wastegate), as a boost controller simply cant make the wastegate open at any lower pressure than where the spring opens.

A bleed valve quite literally 'bleeds' some of the pressure so the wastegate doesnt see it, theres no way of making the wastegate see *more* pressure so that it opens sooner and therefore runs lower boost.

s15, dont know how much but all i know it passed the 1bar, i got zorst, pod, fmic, new clutch that has slipped but fixing it again.

If you've done a FMIC, make sure you have some sort of feed still going from a pressure source back to the wastegate.

Not pressure feed = no boost control

That would be my first place to look.

which vacume do i need to look at, dey all look like they r in place

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On the passenger side suspension tower, you will have a stock boost controller solenoid.

this will have hoses comming in and out of it.

one goes to the wastegate actuator and the other goes to the intercooler piping.

when stock, one of those pipes also has a tiny little restrictor in it to make the boost stay at 7psi.

so..

when you got a fmic installed, if they didn't connect the hose to the wastegate actuator or to the NEW intercooler pipe, you will have no boost control, therefore the wastegate will stay shut causing all the exhaust gases to go through the turbine wheel, making massive amounts of boost.

If it is all connected, they may have changed the hose or hoses from boost controller to new ones to fit the new piping and therefore the restrictor is gone and now you will have about 14-15psi if I remember correctly on my old S14..

so in a way, a new boost controller will solve your problem..

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