Help Turbo Not Holding Boost

[gtst93]

Hi guys last week I upgraded my turbo and I had it tuned yesterday and they found that it is not holding boost.

Basically they set the boost to 17psi and it drops straight away down to 13.5. Then comes back up to 16 then back down and keeps on dropping down to 12psi. that’s with my boost controller but it also does the same without the controller.

Does anyone have any ideas?

The turbo is a trust TD05 18g

[bj_dove]

The turbo is a trust TD05 18g

<{POST_SNAPBACK}>

td05?? bit small isnt it?

[gtst93]

i only wanted 250rwkw without much lag

[blind_elk]

Check the spring in the wastegate controller.

[Robo's]

Shouldnt go up and down like that, it should be progressively. Check your actuator lines , sounds like you have a leak

[BookyVL]

Yeah, check actuator lines, also got a blow off valve? Might be leaking over 12PSI, dropping boost pressure...

Check clamps on FMIC piping you you have a cooler... Im guessing you do running that boost...

Edited November 16, 2005 by BookyVL

[gtst93]

yer i have a trust fmic and power fc and all the other stuff.

have checked actuator lines for leaks also put the little standard hose back on still the same.

Thanks for your help guys will try bov and also look to see if the actuator is rubbing.

[paulr33]

find out what psi rating the actuator is. if its like a 7psi spring and your trying to run 16psi through the boost controller has to work very hard to maintain the balance and it may not be able to keep up as well. what controller u using?

[gtst93]

don’t no what actuator spring is in it but the lowest boost that it will let me run without the controller is 12psi (standard actuator line)

i have a Hks boost controller

[BHDave]

My mates actuator stuck on his td05 as the shaft angled slightly when the wategate flap was open and so jammed the shaft against the bracket.

You dont have any factory boost contollers or that sort of thing hooked up do you? And how is the actuator plumbed in? Can you remove the boost contoller from the loop completely as a test?

[gtst93]

^^ yer done that still the same thing^^

[Dush]

i got the same problem bro, i donno why, its set at 16psi, it reachers it and slowly drops down :S. my car is gettin lookst at tomororw.. we proble got the same problem

[gtst93]

let me no what yours problem is

[T04GTR]

ive seen this before.

check or tighten the wastgate actuator.

with it of the wastgate flap you should have to pull it about 4mm or so to slide it over the flap leaver(what the rod pushes on)

also to stop that anoying boost dropping at hi revs hook the main feed directly to the plenum. not the outlet of the turbo.

[gtst93]

yep we have adjusted the wastgate actuator still the same