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Discussion Starter · #1 ·
Just got my Newsouth Boost Gauge Fitted, and i'm puzzeled by the readings i am getting.

At idol I get about -18 psi, then when i rev the car slightly this goes upto 0.

When im crusing at anywhere below 85mph its between -10 and -18 psi.

When i acclerate off boost it goes upto 0 psi.

when
I acceleratehard the boost goes upto 18 psi sometimes then drops back
down at about 4000 rpm, but other times wont go past 10psi.

Is this normal?
 

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its about throttle position not spped really...

on full chatter ud expect about 18 psi slowly tapering down as the revs go from 4-6k

of throttle it will be in vacuum yes so it doesnt sound like you have any problems.... need to see a log of it tho tbh

only bit im not understand u on is the fact u say when u accelerate of boost it only gets to 0??? thats odd
 

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Your car will only produce boost when under load so when at standstill in neutral your car will be in vacuum state so you will see around -19/20 psi raising to 0 when you rev your engine.When you get going and give it some thats when you will see your engine producing boost.
 

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Your car will only produce boost when under load so when at standstill in neutral your car will be in vacuum state so you will see around -19/20 psi raising to 0 when you rev your engine.When you get going and give it some thats when you will see your engine producing boost.
What Mo said! Spot on there pal!
 

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Discussion Starter · #5 ·
Thanks for the response there guys, seems like its ok most the time.

Any
ideas as to why it will only reach 10 psi sometimes, it happens more
when im working up the gears ie changing at high revs.
 

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Think of it this way.....you boot it in second gear from say 1800rpm and hit ~18psi around 2200rpm, revs keep rising and boost slowly tails off then you change into 3rd gear with revs around 4000rpm, boost won't be anywhere near 18psi again as you've come onto boost much later in the rev range.

4th gear always produces good boost when going up a slight incline, see what you peak at then when it starts to drop off.

Not applicable to your car (mine has a K03s turbo) but look at this log in 4th gear only then 6th gear only then compare it to the one below which was done through the gears (notice it doesnt hit anywhere near 20psi as per the 4th or 6th gear logs):

Posted Image


Posted Image


Posted Image
 

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Discussion Starter · #7 ·
Yeh i see what your saying, since im changing higher up the rev band, it wont peak, shame i cant do a log like yours!

Mine looks ok, still running the old n75 got a n75j ordered, should have been here fri, so i guess things will be a bit diff after that anyway.

Thanks for your help, just wanted to make sure everything is working as it should!
 

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can i ask some questions?

so your getting around 18psi with your map? yes? what do they run on the standard map?

cheers
 

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can i ask some questions?

so your getting around 18psi with your map? yes? what do they run on the standard map?

cheers
AGU - 0.6bar or just over 8.5psi
cheers. what do you think it will run with a custom chippeduk map?

sorry for jumping your post mate. but its a free bump lol [;)]
 

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can i ask some questions?

so your getting around 18psi with your map? yes? what do they run on the standard map?

cheers
AGU - 0.6bar or just over 8.5psi
cheers. what do you think it will run with a custom chippeduk map?

sorry for jumping your post mate. but its a free bump lol [;)]
If its a true custom remap then each car will run differently depending on how much boost the engine can safely handle (eg uprated intercooler, cat & exhaust, cai can run more than a standard setup), so there wont be a definitive amount of boost it will run.Some may spike to 18psi then drop to 12psi some may spike to 18psi then drop to 15, some may spike to 18psi then tail off slowly.A generic map on the other hand may peak at 18psi then drop rapidly to 8.
 

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Discussion Starter · #12 ·
Mine does peak at 18psi SOMETIMES.

It seems to want to pick when i get 18psi, or 10psi max.

Ive done like for like runs, and i cant see any pattern as to why i get 10psi sometimes, and 18 others ...

Do you think this could be indicative of a problem somewhere?
 

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I have a similar problem!! When caining throught the gears ill only get 10 psi ish. If acclerating from lower down the revs its only peeking 14-16 psi. Its all over place at the mo.

Beforehand itd spike at 18psi and run 16psi slowly dropping past 4-5k on the revs.

I believe its a prob with the maf sensor or N75 valve??
 

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Yeh i see what your saying, since im changing higher up the rev band, it wont peak, shame i cant do a log like yours!

Mine looks ok, still running the old n75 got a n75j ordered, should have been here fri, so i guess things will be a bit diff after that anyway.

Thanks for your help, just wanted to make sure everything is working as it should!
does an N75J make a difference then?if so,what difference,and what exactly is it?some kind of sensor?
 

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Mine does peak at 18psi SOMETIMES.

It seems to want to pick when i get 18psi, or 10psi max.

Ive done like for like runs, and i cant see any pattern as to why i get 10psi sometimes, and 18 others ...

Do you think this could be indicative of a problem somewhere?
Get your car on vag com.My car was feeling sluggish and felt like it was pulling back timing when boosting.
Kept getting an intermitten fault on temp sender so swapped it out and now running fine again.No more errors so
Id say its worthwhile getting checked for errors to make sure everything is working fine.
 

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Discussion Starter · #16 ·
Thanks for your help so far guys! the saga continues!!

Just had it on me vag com and no errors!

I got me mate to still in and watch me boost gauge as i drove around.

Sometimes it boosts to 18psi and drops to 12psi, then it will for no reason boost to 12psi and drop to 8psi !!

What should i expect from an upsolute remap for my agu ??

It does seem to feel like its slightly holding back etc when it only boosts to 12psi.

Im confused!! and a bit worried incase its something more serious [:S]
 

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Ok this post has got me a little worried sorry to hi-jack it

My chipped AGU will only seem to peek about 12psi but will happily sit at 10psi all the time.

I know the ECU is self learning is it worth reseting it and give it some WOT to get the boost up a bit more or shall i get hold of a VAG-COM cable for my laptop and do some investigating?
 

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Reading with interest as it turns out my 18T must have been chipped by a previous owner. Guess the chip and companies differ quite a bit and how long ago it was done. Mine must be 4 years old and would still not know if I hadn't fitted a boost guage!! My boost is around 14-16psi and holds 12-13 until high in the rev range. I also run a hybrid GFB (and love it). As for the 10psi sometimes and 18 psi at other, I can only judge this by experience and that it is the size and weight of your right foot. Test this and let me know for comparisons. Accelerate normally = the 10 psi (steady) and boot it = full boost.

Keepin' it smoooth like me 'ed[:S]

Gadge
 

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Discussion Starter · #20 ·
I would refit my standard dv, but since moving home i have no idea where it is!

I think there about ?40 + vat arnt they, bit pricy just for a check, has anyone got an old one i could buy??

Can the engine temp have any bearing on this, could it be a faulty sensor that has not given a fault code?
 
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