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Boost Creep Issues

Sparky206

By Sparky206,
in Engines & Forced Induction

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lotsalag Contributor

lotsalag

Posted
Posted
The standard solenoid isnt even being used, all i have is a vac line hooked straight into the wastegate, so its seeing the same presure as the boost guage. The boost guage is working, i can feel it hit R&R as it hits about 12psi.

The diaphragm is inside the actuator? so it would have been changed when i changed the actuator

Yes the diaphragm is inside the actuator. Did u buy it brand new? i doubt u did.

Either way u cant assume anything is ok, if u overlook a potential cause u might be chasing this problem forever. lol

It wont take long to see if the actuator holds pressure anyway.

Seriously tho, have u had it a workshop? or had it tuned at all with the highflow? tune wont cause this, but im surprised ur car hasnt either

a) blown up

b) running like a bag, hitting fuel cut etc all the time

c) maybe its simply hitting R&R and this is having a massive effect on boost control

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rob82 Mentor

rob82

Posted
Posted
yes, mine would spike to about 17 psi, even removing my boost controller it would go to 14 psi. as soon as i got the injectors and power fc fitted, i could tune it down to 11 psi no problems, i got a highflow turbo as well. i may be wrong but you have all the same problems i had, i even changed my split dump to a bellmouth but nothing changed, everyone was saying ,check the actuator, check for leaks, but in the end it was the tune, a rich tune will cause extra gasses in the exhaust spooling up your turbo beyond what your wastegate can handle. once it is leaned out and ignition sorted it should go away

my saga

http://www.skylinesaustralia.com/forums/Ov...ml&hl=boost

It's more the retarded ignition event that will help spool the turbo. Unless it's that rich and retard that the combustion event is occuring in the exh - that's what we call anti lag.

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ClutchBurndout-:( Grand Master

ClutchBurndout-:(

Posted
Posted

i had the exact same problem as the OP, so i installed an ebc, and it seemed to hold its boost a lot better.

from what i learnt trying to figure this out just like the OP is, i think it was because at around 10 ish the f/a mixture changes and that effects the output which your turbo/wastegate dosnt understand nor see, so it overboosts.

but another thing i remember, was that the stock springs in the actuator become weak after a while and dont seem to hold as stable? does that sound right?

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PM-R33 Grand Master

PM-R33

Posted
Posted

A tune can cause this. Heavily retarded timing and shit loads of fuel will cause boost to go all over the place. As others have said, that is what antilag is. Mine is currently doing this because we have pulled the timing out of it. Not saying this is the OP's problem, but just stating it can happen.

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