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Hi all,

No doubt some of you know Im having problems with an RB25 overfueling at idle. Injector pulse at idle is 7ms! Car runs in limp mode, idles smoothly & does not smoke (although it smells a bit rich) until AFM wires are pulled or played with, then it starts pouring black smoke, hunting real bad & AFM signal voltage sits on around 2.4v at idle... Obviously I strongly suspect AFM circuit but AFM & ECU have been swapped & AFM wiring has been checked for resistance to ECU, resistance to earth, shorts, etc & I cant fault it! Have also tried removing AFM plug & hooking wires straight to AFM...

Anyway if things dont get sorted soon Im wondering if I could go for a remap & get fuel maps changed to provide the correct amount of fuel?

I know its a band-aid solution & probably not ideal & I would much rather find & fix the problem but this is getting ridiculous & Im getting desperate. Have no idea whats going on & neither does anyone else it seems...

Just wondering what peoples opinions are on this?

Thanks

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https://www.sau.com.au/forums/topic/296180-remap-to-mask-overfueling-problem/
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sucks that you are having so much trouble with this man.

the only thing that i can think of is a knock sensor kicking in, it won't show up as a fault on the ECU. you can test it if put a 1M ohm resistor between the signal wire and ground thats tricks it into think everything is fine.

what is injector pulse and AFM voltage supposed to be?

i got no idea if a tune will fix it, trent from status would be the man to talk to though.

seriously just take it somewhere, any workshop worth a damn should be able to sort it.

Remapping aint gonna do shit, i know i wont touch a car for a tune unless it is bug free... i doubt anyone else would either.

Edited by URAS
sucks that you are having so much trouble with this man.

the only thing that i can think of is a knock sensor kicking in, it won't show up as a fault on the ECU. you can test it if put a 1M ohm resistor between the signal wire and ground thats tricks it into think everything is fine.

what is injector pulse and AFM voltage supposed to be?

i got no idea if a tune will fix it, trent from status would be the man to talk to though.

Yeah... I know...

OK, will try that. Willing to give anything a shot...

Injector pulse width at idle should be 2-2.8ms & AFM signal should be around 1.5v

seriously just take it somewhere, any workshop worth a damn should be able to sort it.

Remapping aint gonna do shit, i know i wont touch a car for a tune unless it is bug free... i doubt anyone else would either.

OK, thanks for the honest opinion. Wanted to hear from someone like yourself who actually tunes cars...

Figured it was worth a shot asking. Actually a mechanic myself so as you can imagine, hate taking my car to the shop. Problem is I rebuild automatic transmissions so dont have much in way of engine diagnosis tools at work... Also dont trust many general mechanics knowledge of imports...

What is your going rate for this sort of thing? I am just in Cranbourne & work in Sth Dande too... (A & B Automotive Remanufacturing)

If you dont want to discuss prices on here drop me a PM or I will call Monday. Will probly also be after a remap once this is all sorted too

Opinion? Take it to a professional.

It'd be lucky to cost more than $250

Yeah, I hope your right...

ROFL I was about to suggest you just take it Trent. Really is worth the wait. It has been my (and a number of my friends) experience that someone with the level of experience of Trent is going to diagnose your problems in a fraction of the time with a lot less mucking around. From there it is usually a relatively simple process to rectify. In the Victoria section is a list of other workshops that might have time to take a look (although it seems everyone is flat out before xmas!).

any competent workshop that knows auto elec and skylines can fix it

why on earth would you wait 1.5 months? there must be a dozen recommended sau vic workshops, check the thread at the top of the vic section

thanks for the support guys i appreciate it alot but like i posted earlier there are plenty of guys who should be able to sort it quick smart, i seriuosly would not wait 1.5 months so why should you.

My business revolves around tuning and engine building everything else takes second tier to that, i can usually squeeze in tuning and so forth but i cant push around tuning jobs for diag as its not my core business.

These are workshops i could reccomend to get the job done fuss free;

RACEPACE

CREATD

RE CUSTOMS

HI TORQUE

CHASERS

Edited by URAS
I would love to help you out but im booked into the new year, sorry. Try Re customs or hi-torque.

Any chance for a full power fc tune for a r33 some time in december trent? Ill give you a call during the week.

Edited by skline01999

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