9n3 Boost adjustment issue

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Pologticrazy
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9n3 Boost adjustment issue

Post by Pologticrazy »

So i had the engine rebuild and a new turbo. Before the rebuild the car was boosting around a bar and settling on 0.8. The new engine has done round 10000km and i have been struggling to get the boost back up to previous setting as mentioned. The actuator has been adjusted but i cannot get the car to boost more than 0.5. Took the car to the shop that rebuild the engine and they said to adjust the boost they will have to take the turbo off. This doesnt sound right to me? Is there a way that they maybe bypass a sensor or adjusted something so that even if the actuator is being adjusted the boost will be 0.5 and nothing higher. Any suggestions before i have to spend a hell of a lot of cash to fix this.
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Re: 9n3 Boost adjustment issue

Post by THANAS »

Whereabout are you based?
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Re: 9n3 Boost adjustment issue

Post by Pologticrazy »

Hi
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Re: 9n3 Boost adjustment issue

Post by Lodewyk »

Howzit man pop me a message i can assist you and see if we can pinpoint the issue rather than spending unnecessary money on it.
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Re: 9n3 Boost adjustment issue

Post by panic-mechanic »

Did they plugin the n75?
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Re: 9n3 Boost adjustment issue

Post by Pologticrazy »

The N75 is plugged in. Ive read somewhere that if the fuse for the N75 is blown that would also restrict the boost to .4 bar. Do you guys know which fuse this is? Maybe i should also look at getting a new N75 valve.
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Re: 9n3 Boost adjustment issue

Post by Jueshen »

yes that is correct, i had a blown n75 fuse and boost was restricted to 0.4 bar
drive side panel by door
not sure which fuse
just check each fuse one by one so you know where to put it back
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Re: 9n3 Boost adjustment issue

Post by Lodewyk »

Make sure it is the issue before spending money replacing it. Have you scanned for errors? Run logs yet?
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Re: 9n3 Boost adjustment issue

Post by Nikz_tsc »

Possibly they have incorrectly plumbed the N75 valve. Check that there first. With the plug facing you, Boost source should route the "underneath" of the valve, left of valve should feed to actuator and the other side should bleed into the turbo inlet.
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Jueshen
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Re: 9n3 Boost adjustment issue

Post by Jueshen »

and remember if you disconnect the line from n75 to wastegate you will overboost, basically turbo will keep boosting till it goes boom.
basically thats how i tested to see if my turbo was still ok..
after fitting another n75 still no boost
then i checked the fuses, and problem found
but i had a boost gauge and did not let boost go over what it usually did

lol neat trick like in f&f latest f&f movie put a clip to your line to wastegate and pull it to win a race
burn car as well
lol
i wonder how many guys will pull their line to wastegate after that
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Re: 9n3 Boost adjustment issue

Post by Pologticrazy »

Nikz_tsc wrote:Possibly they have incorrectly plumbed the N75 valve. Check that there first. With the plug facing you, Boost source should route the "underneath" of the valve, left of valve should feed to actuator and the other side should bleed into the turbo inlet.
I checked and saw that the boost source and the feed to the actuator was swopped around. The car is boosting 0.9 on 93. Luckily the tank is on reserve and will fill up with 95 and then adjust the actuator another turn to turn and a half to get to a bar.

Thanks guys for the help!!!!
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