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about a month ago, i did the little bodgy mod ( http://www.skylinesaustralia.com/forums/sh...ead.php?t=42895 ) which basically gives you constant 7-8 pound boost. which i was quite happy with the result.

about a week ago, on my way to work, i noticed i was getting no more than 3 pound boost (wouldnt go over the line between 0 and 7 on the stock boost guage)

once i got to work i popped my bonnet and saw that the red wire (which was inside the black one to be earthed) became loose and wasnt connected to earth.

i went and purchased a boost controller assuming that my boost solenoid had carcked it but that hasnt fixed the problem..

could it be my computer which is restricitng it to 3? i`m really confused!

any suggestions as to why i cant get over 3 pound would be greatly appreciated!!

babs

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The stock guage isnt in psi, its in mmhg. +7 is 14psi.

With the earth wire hack (that i wrote up) you should go just on the 3/4 line or like 1 spec above it which is about 7/8psi. If you are in standard mode (no wire hack or below 4500rpm in normal mode) you will be 1/2 between a 1/4 and 3/4 which is about 5psi.

If the wire comes loose and doesnt earth then the solenoid is in a closed state which is 5psi.

The ecu will try and ground itself above 4500rpm but because youve hacked the wire it wont do anything and just keeping plodding along.

Solution?

Fix the loose earth wire or return it back to factory setup. Theres nothing wrong, simply the hacked earth that youve done has come loose and no longer working, ie: the circruit isnt complete anymore and the solenoid is closed (5psi mode)

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https://www.sau.com.au/forums/topic/47064-boost-prob/#findComment-952354
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ok, thanx for the reply..

but that still does not explain why i cant adjust my boost with my dual stage boost controller? with the switch on or off i still get the same amount of boost (just below the 3/4 line) which u pointed out is infact 7 pound..

also how come once i did the wire hack i was getting aprox 7/8ths (close to the +7 on the guage..) and i understand the concept of earthing the wire, but what is the red internal wire for (wrapped inside the black one)

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