Boost

[Markturbo]

i manage to get my boost turned up on my tubby to 1 bar but it doesn't hold a bar of boost it drops straight back to 10 - 11 psi of boost i think half way in between 0.5 - 1 bar of boost i have filter, downpipe, exhaust but the flexi pipe is blowing colder grade plugs and a fcd

any ideas why it doesn't hold the turbo was only rebuilt 6-7 months ago ;)

[Jimlad]

possible a soft actuator ?

[Markturbo]

is there a way the actuator can be checked you don't think its anything to do with the flexi pipe blowing i have just bought a new exhaust which will be here next week

[Bibbs]

Flexi wouldn'tmake you loos that much boost (I'd have thought).

Only way to check an actuator is to get a hose on the pipe and pressurise it and see when it releases :)

Get a FCD and G-valve and it'll be fine :D

[Markturbo]

i for got to say i have a g valve and fcd and the boost goes up to a 1.0-1.1 bar boost but then just gradually drops to bout 11 psi i thought it would hold a bar boost all the way threw i will see what happens when i get my new exhaust on next week

[boundsw]

mine did this when i 1st turned up the boost.

was my actuator, just couldnt hold the wastegate shut !! was knakered.

[newtomymr2]

sorry to hijack your thread mark but I'm in the middle of fitting my g-valve as we speak or type whatever, anyway, how did you get the valve to fit, did you go from under the car by any chance, or fit a longer length of hose, cos coming from the top of the engine I just cant see how I will ever get the %$(ler on :ffs: I've removed the airbox as I'm fitting an induction kit at the same time, so I have nicked as much room as possible, just cant seem to get the the b :censor: d, theres two hoses just above the hose that runs from turbo to actuator, its driving me up the wall......who's idea was it to vaccum pack an engine into a car then release the pressure to make it expand into every corner of the car :ffs: :ffs: :ffs: :ffs: :ffs: :ffs: :ffs: ......bleeding nuckles :ffs: :ffs: :censor: :censor: :ffs: :censor: :ffs:

[Markturbo]

i had someone fit all my g valve and other parts.

sorry i cant help i think i will get my actuator checked or get a new one fitted,

will i need an uprated one or will a standard one be fine where is the best place to but one from prices ect ;)

[Bibbs]

fitting a G-valve is a knack .. refitted mine in 10 mins ..

[newtomymr2]

I'll get in there again tomorrow,

I dunno about the actuator mark might be worth uprating if you're going for bigger boost in the end, but I think peeps have issues with uprated actuators being too strong for a pretty standard set-up

[Fizz]

mine did this when i 1st turned up the boost.

was my actuator, just couldnt hold the wastegate shut !! was knakered.

←

Hmm.... Wonder if mine is knackered...?

Mine does exactly the same... it hits 16Psi in 1st and 2nd gear and then drops.. 3rd and 4th hold at 11/12Psi...

I knwo that the true boost is found in 3rd and 4th... but the 'flash' boost to 16Psi.. i dont want to risk that going up higher... :s

I want the rest Psi to be at 15 but that would mean my car would be flashing up at 18Psi at least..

[EarL]

The symptoms you described are exactly what happens when the actualtor goes "soft". My g valve is set to peak at 1.2 bar and holds this until the redline in 3rd and 4th, but the actuator is new and the turbo is a stage 1 CT20b.

As Bibbs mentioned, you could test the actuator by feeding a pipe onto it and pressurising the unit and see when it leaks off.