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What Is Your Theory?

Daboss

By Daboss,
in Engines & Forced Induction

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Daboss Experienced

Daboss

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Posted

Hey forum just after some intelligent theories as I have my own and just wanted to compare and see if I am on the right track. Ok its a 95 gtst with a z32 afm and an untuned safc just setup so the car can start with the z32. Here is the problem car makes positive boost pressure but goes nowhere. Checked all piping and hoses thoroughly and there are no tears or leaks. Now I didn't check to see if it would make power by gradually pressing on the throttle but when mashing the throttle boost builds but there is no power.I am thinking that the ecu, which is stock is going into some fail safe mode as it is seeing too much air/voltage coming from the z32afm which it is not tuned for. Also boost control is set for 10 psi but when in second flooring it by 3000 rpm only get to about 7psi and as I stated earlier car has no power.

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NZM.031 Grand Master

NZM.031

Posted
Posted

i have had the same problem... ignition timing was retarding itself big time due to a fault with the afm... it was making all the right noises... just not going fast.

are you positive you have the safc set to z32?? is the z32 afm new or 2nd hand?? and is the wiring job good?? did you splice the wires in with the ecu or make a good solid soldered connection.

the safc wont make a difference if its tuned or not, but if its not telling the ecu that its a z32 afm then it will be running lean, and retarding the timing to suit

cheers

Linton

Daboss Experienced

Daboss

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Posted (edited)
i have had the same problem... ignition timing was retarding itself big time due to a fault with the afm... it was making all the right noises... just not going fast.

are you positive you have the safc set to z32?? is the z32 afm new or 2nd hand?? and is the wiring job good?? did you splice the wires in with the ecu or make a good solid soldered connection.

the safc wont make a difference if its tuned or not, but if its not telling the ecu that its a z32 afm then it will be running lean, and retarding the timing to suit

cheers

Linton

The z32 is used and the wiring job isn't soldered but spliced in by butt connectors so I would say it is a solid job and the safc is set to z32 two in four out. So a z32 thats installed onto a stock ecu by an untuned afc neo wont cause the car to run lean? What I mean by that is if the neo is not uned but just set up to in the afm section for a z32.

Edited by Daboss
NZM.031 Grand Master

NZM.031

Posted
Posted

if the safc is set to the z32 afm... then it will adjust everything and tell the ecu that its all good... if its not soldered... its not good. if youve used those simple wire splicing connectors then that could be it... they dont work at the best of times. i always solder stuff in, especially when its for the ecu. how have you wired up the z32 afm?? in the same way?? if so, that could be it aswell.. if you hard wire it, you can see the wires a physically touching each other, there is a good connection there. solder it and heat shrink it, then wrap it in tape or condute. is it a safc 1 or safc 2?? buttons or joy stick??

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