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I just got my car back recently, noticed a few things wrong with it.

Feels like its struggling and on 5 cylinders.

Before someone says coilpack it struggles throughout the rev range, low and high rpm.

I have gotten it back from the panelbeater since I got a respray. I also got them to install my fmic and highflow turbo.

Once I got it back I noticed that my turbotech boost controller was missing its spring, they must have opened it and lost it.

I have the usual mods like full 3" exhaust, front/dump, remapped ecu.

What is the worst thing that could happen if the boost controllers spring is missing?

I have removed it and put it back to the stock setup, still that didn't solve the struggling engine problem.

And when the boost controller was on or even the stock setup, on the boost guage it wont even go above 0. Its like its restricted from going past it because when you drive it, the gauge will quickly go to 0 then stop there.

Does anyone have any ideas?

The last resort I want to do is to give it to a specialist and all he would probably do is to go through the whole list of a 100k service to figureout the problem. Well thats what the panelbeater told me to do anyways, It might just need a tune

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When I drive the car it feels like the turbo isn't even working with the stock setup(boost) but when I had the boost controller on with the missing spring I do notice that the turbo just spools but never releases because most likely the spring isn't there.

So that marks out that the turbo is fine, how do you check if the wastegate actuator is working properly? Would I have to remove the turbo again? Hope its working because then I have to pay someone to remove it again

I checked and it seems like its all together properly.

When on neutral revving, it flutters now since I have tightened the intercooler hoses.

That should mean that the wastegate flap should be working correctly right?

i had a similar problem, but my was a easy fix there was a crack/leak in the vacuum hose leading to my boost guage. replaced it and it was fixed but same problem.

Boost wouldn't go past 0.

BUT i could hear there was leaking as soon as i opened the engine bay which didn't sound right.

well only other option is a leak in the hosing only seen during boost conditions

as GT shortie said, check thew vacuum lines are not split and are hooked up correctly... ie without controller - straight from IC pipe or plenum direct to the actuator

Oh ok thats good to know.

So that means my afm is fine

I guess I'll get my head stuck in the engine bay tomorrow and figure out whats wrong with it.

Do you think the afm or coilpacks have something to do with the car struggling throughout the rev range?

If it won't go past 0 then you have a leak somewhere. It won't go past 0 because 0 (on the gauge) is atmospheric pressure and when the compressor tries to pressurise the air past atmospheric, the pressure difference just forces the air out through wherever your leak is.

Coil packs will not restrict boost like that. Neither will the AFM.

Start up the engine, get under the bonnet, look and listen carefully for hissing and if you can't hear it at idle, open up the throttle a few times and it should become obvious.

Edited by govich

did the new turbo have a new wastegate actuator? if it did then it may be the problem. it may be stuck in the open position, or if it is adjustable, needs to be set to a boost level.

it may also be one of the intercooler pipes isn't in the silicone joiner properly, or the joiner is split.

also if there was no spring in the boost controler, that would just make it run at the boost pressure of the wastegate.

Yea I'll check it up once I get another turbotech boost controller.

Just waiting on delivery.

I can't seem to hear any leaks.

Maybe because stock boost only. I have a fmic and a highflow vg30.

Wouldn't 5psi-7psi to hear?

is the stock guage connected? (check that)

check for intercooler pipe leaks (use soapy water)

check for boost signal leaks or tubes undone (ie open to atmo)

is the actuator had no signal youd be in unlimited boost mode

Hi guys,

I finally got myself another turbotech boostcontroller. I just recently installed it, took it for a drive and still wont go past the 0 mark.

All the intercooler pipes and vacuum hoses have been checked. Seems to be all fine.

Does anyone have anymore ideas to whats causing the problem?

If the turbo was installed incorrectly, could this be the problem? Hopefully it is installed properly.

Does this look right?

post-27024-1158742687.jpg

Sure as God made little green apples, there is a connection somewhere in the intake plumbing that is not connected properly.

Had the same problem when I re-installed my engine after a rebuild.

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