Still got Boost Probs!

[Jit]

Just when I thought I had figured it, something else goes wrong...

Now before I start, let me say that my boost gauge is plumbed thru the UIM (the bit thats normally plugged) so Im assuming tha the readings from the gauge actually show the boost in the UIM?

Basically the car is faster when you back off the throttle and then go back on it part throttle. On WOT, it doesnt want to know on either turbo.

On second turbo the gauge registers 0.68-0.69 bar.
And in the second turbo sonze you can definitely hear what sounds like a leak!?

Does anyone have any ideas before I strip the whole car down and replace every single bloody hose?

Cheers

[TRex]

Hey Kid, give me a bell tomorrow if you are free and maybe come round mine later on, and we\'ll see if we can beat that Turbo\'s arse into working properly! http://www.smileycentral.com/?partner=ZSzeb008_ZNxdm798AXGB" target="_blank">http://smileys.smileycentral.com/cat/15/15_4_102.gif" alt="I've Got It" border="0">

[Jit]

yeah if im free!! Got an exam monday morning so probably wont be You about during the week?

[TRex]

Hey bud, I\'m around the latter part today and next week will have to be the back end of the week(Thurs --->)

 Those Turbo\'s are crying out for bonding dude, \'Parallel\' is the way to go, you know you want too!  :Giggle

[Jit]

lol, i got exams on monday (which rules out today), friday (which rules out the later oart of the week) and then the wednesday the week after! And two days later im off on holiday!! ANd i still got to get that bloody shell off my drive!!!

[dj_dee99]

Seem to be having the same problems as me. boost drops when 2nd turbo should be kicking in. Still not got mine sorted!
 
I also seem to get a lack of boost after gear change unless I use part throttle, too.

[Jit]

Does yours register around 0.6-0.7 on the gauage?

[dj_dee99]

Pretty much either side of 0.6.

When you\'re getting no power till you go half throttle, are you getting the sonar/cow moo sound? I find that if It\'s holding back when on WOT, if I clutch it so the revs drop down, then the power will return on acceleration. Obviously, it\'s no solution, though. Still gotta work out what\'s going on.

[Jit]

sounds like what im getting but not a sonar sound...more of a hissing of air escaping!
Im gonna strip it down when i get back from holiday so hopefully it wil sort itself out then!

[Jit]

cos im a bit new to all this turbo malarkey...if the boost gauage is shwping 0.67 bar in the second turbo zone, could it be that thsi 0.67 bar is only from the first turbo and that the 2nd may actually not be online?

[dj_dee99]

That\'s what I\'m thinking is happening. Usually, it should hit around 0.8 bar. Then at 4500 rpm, there should be a drop to 0.6 then back to 0.8 as the 2nd turbo kicks in. So I\'m guessing the 2nd turbo is possibly not coming online at all.

[rx-paul]

im having a similar problem when i floor it i get i sort of boost serge upto 0.7 but no real kick my boost guage hisses a bit then it drops down to 0.5-0.6 before theres a smell of petrol iv changed all the intercooler pipes with samco and checked everything else i can think of but i just ant cracked it yet

[Jit]

lol....sounds about right.....i definitely get a surge from the 1st turbo but only realy on part throttle....never on foot to the floor WOT and never when you "kick-down" so to speak....
I know one vacc line keeps coming off so ill replace that with samco, but i still cant get my head around the 2nd turbo!
Doesnt matter now anyway as itll be stripped down in less than 4 weeks now anyhow!

[nikp]

If we\'re talking about a standard setup, then standard boost is actually more like 0.7 bar, not 0.8

(10psi, where 1 bar is 14.7psi, which equates to 0.68bar)

If you\'re not sure if your second turbo is coming on line or not, and you have a mechanical boost gauge, you could plumb it into the second turbo for troubleshooting purposes. It might indicate something useful.

[rx-paul]

is there any way to test the actuators on the turbos?