No Boost - Rev 3 Turbo

[iainh99]

Evening all

I'm getting very little if no boost at all from my ct20, I'm also getting a rattling noise when the very little boost does come in. its been no trouble until now so not sure whats happened, i drove one day and it was fine the next no boost.

What I've checked so far:
examined the turbo from both side it spins freely and has no play above normal, both compressor and turbine wheels have all the blades.

none of the pipes are leaking air

the dump valve is working

all the cylinders are firing and have good pressure.



Does any one know what the affects would be if the actuator died?

Cheers

Iain

[Blue_5]

Do you have the cat still in place?

[iainh99]

no mate, replaced it with a de-cat pipe about 3 months ago.

[Blue_5]

If you've checked the exhaust side, im assuming the wastegate door was seated ok, and still sprung shut? Did the intake and exhaust impellers bot thurn together?

Im certainly no expert, but if the actuator had failed, i would have thought it would no longer open the wastegate door, and you would overboost.

[iainh99]

Yes the wastegate was closed and still sprung. I'm not sure how the actuator works..... I'm going to pressure test it tomorrow and see if it hold pressure or vents its..... if its the later I guess I have my answer.

If it hold pressure then I'll have to take the exhaust side off again and see if the compressor and impeller are still connected..... I hope i've not snapped the shaft..... but thought I would have shattered blades off the impeller first.

Thanks for your suggestions

I'll post the pressure test results one done.

Cheers

Iain

[iainh99]

I don't believe it!

Tested the actuator and all was well.

Thought i'd see if the DV was at fault so disconnected it and put all the pipework back on for the standard DV and jobs a good'un. Seems the Bailey DV was venting all the boost to atmosphere.

Sorted.

Blue_5 thanks for your suggestions

Cheers

Iain

[Steve-O 2007]

get a hks ssqv, the more boost the tighter it seals shut

[Blue_5]

No problem - glad it was an easy fix!

I had a Baileys DV on my old GT4 that did that occasionally - i took it apart and gave it a good clean and lube, it seemed fine after that.