Boost Issue?

[A L 3 X]

Got a little boost issue atm, well...I'm hoping its little.

I noticed today when driving down the bypass if i gave it wide open throttle in second, on my boost gauge it would rise to around 0.7 as usual, but as the revs climbed higher the boost started to drop down towards 0.5 and a whistling sound could be heard.

I only noticed it today but it may have been present for a while because I was driving quite spiritedly tonight, I then took my HKS ssqv off and swapped it for the standard DV to see if that ruled out the problem, which it didn't, so the DV isn't leaking I assume, but the weird thing is before I bought the HKS, I had the standard DV fitted with a cone filter, and there was a chatter noise, upon returning to this setup for the test today there was no chatter sound but just a faint puff of air sound on closing the throttle, not sure if this is related to my problem but could anyone help?

A mate has suggested something to do with the standard actuator?

Cheers

[ollie454]

Boost leak mayb

[Amjad]

Sounds like a boost leak, you could possibly have a weak actuator also

[A L 3 X]

Sounds like a boost leak, you could possibly have a weak actuator also

Any ideas where to look for on the boost leak, cars all standard besides a hks ssqv(which ive tried taking off) a boost gauge and a cone filter fitted on the standard piping?

One thing is the car still feels okay to drive but i spose if its only dropping to .5 near the top end its not that big a leak?

Cheers

[Amjad]

Just check the hoses on the turbo/cooler system. Maybe check the vacuum hoses too? If that doesn't sort it it might be your actuator but I don't think they emit a noise when weak, they just don't hold boost

[A L 3 X]

Yeah i didnt think the actuator would make a noise but I can't see where it'd be leaking?

Its like say if i boot it in second, it will start boosting, climb to full boost and stay there for a bit then start to slowly drop, and when it gets just above 0.5 it starts making a whistling noise, at this point were just before the redline and i change gear...

Could it be where the factory dumpvalve mounts to the efi pipe? Because i'm using that with the vacuum and dv hole blocked up to seal the EFI pipe and to breathe the oil from the rocker cover, but theres is a little oil from the breather pipe around the edge, but i assumed this was for sucking air in and wouldnt leak air from this point?

If not I can't really think where else it could be

Do they sell vacuum hose in motor factors or halfords as i might replace all the weak looking stuff.

[A L 3 X]

Also, is the fact the standard dv and cone setup arent chattering to do with this issue?

[A L 3 X]

Today I refitted the dump valve and replaced the vacuum lines going to it, and the only perished looking one behind the inlet mani. I also loosened and then tightened the 4 hose clips holding the top mount to the turbo side and inlet mani, and I tightened them really quite a lot this time, but the issue is still there, I really can't see what the problem could be if it is a boost leak?

[A L 3 X]

Been having a little think about this, its really quite a slow drop in boost, it kicks to 0.7 quite quickly and then slowly drops to 0.6 and not much lower by the time its hit the redline, and the high pitched noise only occurs close to the redline, so whether im overexagerrating this I dont know?

I've read somewhere that the standard boost on a glanza is 0.65, i've removed the boost restriction so dunno if this means it will be 0.7 or should be unaffected? I was thinking maybe its rising to 0.7 via boost creep, and then dropping back to 0.65, and then maybe my actuator is weak causing it to go to 0.6, and maybe the noise is just normal for high revs, or is this not plausible?

[Amjad]

Sounds like actuator but that sound has me stumped tbh!

[A L 3 X]

Thats what i mean mate, if there was no noise then actuator would be most likely the problem, but its strange this noise is there, i mean i've never driven another starlet so can't compare, it might just be because im right at the redline I dunno, it may not be a whistle just like the engine or turbo screaming but its deffo like a high pitch noise, its not immensely loud but is noticable with the radio off and over the road/engine noise?

A mate said that the standard actuators are known for dropping the boost in high revs, so this certainly points to that as it isn't dropping much boost at all, just the noise?

Is there any other places I could check for boost leaks or an easy way I can check with the car stood still and me looking in the engine bay? Or if not is there anything else boost related that could cause the noise? on TGTT someone said the turbo but it only makes this noise at really high revs and the car pulls far too well for me to think the turbo is majorly bad?