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Turbo producing 0.4bar boost???


Duffman

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Me and a mate removed the 2nd turbo at the weekend and it was cooked...no blades left on the exhaust side. I will get some pics uploaded.

 

Replaced the turbo and its boosting now to 1bar intermittently. What I mean is when I floor it as it's an auto it drops a gear and only shows 0.5bar boost...its not until it changes up a gear where the boost kicks in and it hits 1 bar. Don't think it done this before. Maybe me just being paranoid but could anyone advise if there is anything else that could be fooked to cause this. Have still to fit my Walbro fuel pump but don't think this could be the cause

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I didn't have that issue personally but it sounds like its linked to the IACV. Some people have an issue where if you are at 3-4k rpm and you drop a gear taking you over the 2nd tubby online rev range the 2nd turbo doesn't come in. Its not until you lift off and put your foot down again that it finally does. As far as i know this is normally an issue with the IACV VSV.

 

One quick and easy test to do is the 5 min ttc mod. This will let you know the pressure tank is ok along with all the vac hoses etc. If you do the 5 min ttc mod then take it for a run the IACV and the EGCV should be held open once coming to a stop. If they are not then the system is not holding pressure.

 

Give it a go, if all is fine in TTC then i would blame one of the VSV's. Hope that helps :)

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Will try TTC modealso going to check all vsv's again & double check them

 

I didn't have that issue personally but it sounds like its linked to the IACV. Some people have an issue where if you are at 3-4k rpm and you drop a gear taking you over the 2nd tubby online rev range the 2nd turbo doesn't come in. Its not until you lift off and put your foot down again that it finally does. As far as i know this is normally an issue with the IACV VSV.

 

One quick and easy test to do is the 5 min ttc mod. This will let you know the pressure tank is ok along with all the vac hoses etc. If you do the 5 min ttc mod then take it for a run the IACV and the EGCV should be held open once coming to a stop. If they are not then the system is not holding pressure.

 

Give it a go, if all is fine in TTC then i would blame one of the VSV's. Hope that helps :)

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Me and a mate removed the 2nd turbo at the weekend and it was cooked...no blades left on the exhaust side. I will get some pics uploaded.

 

Replaced the turbo and its boosting now to 1bar intermittently. What I mean is when I floor it as it's an auto it drops a gear and only shows 0.5bar boost...its not until it changes up a gear where the boost kicks in and it hits 1 bar. Don't think it done this before. Maybe me just being paranoid but could anyone advise if there is anything else that could be fooked to cause this. Have still to fit my Walbro fuel pump but don't think this could be the cause

 

Glad to hear your getting there mate :)

 

Such a frustrating car when it goes wrong .

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Not had a chance to try it yet mate.

 

'Bigbloodyturbo' is posting me 4 of his spare VSV's to try :) good of him to do that. Hopefully i'll receive tomorrow

 

It takes literally 30 seconds to do though and will tell you if the VSV's are even needed.

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Just because I don't have access to an airline so can't open the actuators

 

Ahh no your getting mixed up buddy. The 5 min ttc mod is much simpler, you just swap over 2 of the vac pipes and its job done :)

 

Take the line that goes into the IACV VSV and plug it straight into the IACV actuator (from the vac rail to the actuator) that takes the IACV VSV out of the equation.

 

Do the same with the EGCV actuator, straight from the vac rail into the EGCV actuator. That takes the EGCV VSV out of the equation.

 

Job done :)

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Ahh no your getting mixed up buddy. The 5 min ttc mod is much simpler, you just swap over 2 of the vac pipes and its job done :)

 

Take the line that goes into the IACV VSV and plug it straight into the IACV actuator (from the vac rail to the actuator) that takes the IACV VSV out of the equation.

 

Do the same with the EGCV actuator, straight from the vac rail into the EGCV actuator. That takes the EGCV VSV out of the equation.

 

Job done :)

 

 

Think I know what you mean will give it a try tonight...those are the two VSV's at the back on top of the engine bay aren't they?

 

Should I unplug the VSV's as well?

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Think I know what you mean will give it a try tonight...those are the two VSV's at the back on top of the engine bay aren't they?

 

Should I unplug the VSV's as well?

 

No, the EGCV VSV is at the front of the engine, its the one with the smaller vac pipe running from the rail. The EGCV actuator is the big one down inbetween the first and 2nd turbo's.

 

The IACV is the one at the rear top of the engine. The smaller one of the 2.

 

If i'm home before you i'll dig out the guide :)

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