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PLEASE HELP!!! Injector duty is 84%

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Old 09-30-06, 08:12 PM
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ninja

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Exclamation PLEASE HELP!!! Injector duty is 84%

I just recently installed a greddy 3 row fmic and i took the car out for a test drive and according to the commander, the injector duty is 84%. Is this good or bad? Any thoughts/suggestions? Thanks

By the way my car was tuned for 12psi prior to the installation of the FMIC.
Old 09-30-06, 08:15 PM
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I've hit higher than 84% numerous times.
Old 09-30-06, 08:44 PM
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Originally Posted by BoostedFd3s
I just recently installed a greddy 3 row fmic and i took the car out for a test drive and according to the commander, the injector duty is 84%. Is this good or bad? Any thoughts/suggestions? Thanks

By the way my car was tuned for 12psi prior to the installation of the FMIC.
It's ok. you want to keep your max inj cycle at 85% or less. If you start hitting 90's then you need to upgrade to larger injectors.
Old 10-01-06, 09:24 AM
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You're fine. Stock side feed injectors can run higher duty cycles b/c they are cooled by the fuel, so it's harder for them to overheat and stick open/closed. You lose tuning control though above 85-90%, so that you're essentially at wide open 100% duty.
Old 10-01-06, 05:36 PM
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thanks guys...

also after installation of the Greddy FMIC...i was hitting 15-17 psi...i am only tuned for 12psi...what can be wrong? intercooler?
Old 10-01-06, 06:45 PM
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17 psi on stock map sensor? what is your complete list of mods? I recommend you not stomp on the gas at this point, you're asking for a blown motor as-is.
Old 10-01-06, 06:49 PM
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my mods are: Greddy 3 row fmic, koyo radiator, streetport, downpipe, midpipe, rb duals, apexi intake, greddy pullies, pfc + commander tuned for 12psi...
Old 10-01-06, 07:19 PM
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Lemme guess - the boost gets to 12 relatively quickly, then just keeps rising and rising and rising? And this is on stock turbos?

If so, you have a bona fide case of boost creep. You're really lucky you haven't blown your motor. Quit boosting hard until you can pull the turbos and port the wastegate. Read about it in the FAQ.

Dave
Old 10-01-06, 08:45 PM
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good advice in this thread! i definately agree with the others. u dont want to go wot again until u get your boost control issues resolved.
Old 11-27-06, 06:49 PM
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Hey Guys... I took a picture of my peak output from my PFC~~
It says 100% Injector Duty however I heard that this is not a good sign.
So... now what do I have to do? Get bigger injectors?
I'm really a newbe on the injector part of this car so if I do need to upgrade it can anyone please explain to me what I need to do exactly? I really appreciate it guys~~
Thanks

Old 11-27-06, 10:31 PM
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idk, a 3 row is kinda pushing it for only 12psi :/
Old 11-27-06, 11:11 PM
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Originally Posted by akiratdk
Hey Guys... I took a picture of my peak output from my PFC~~
It says 100% Injector Duty however I heard that this is not a good sign.
So... now what do I have to do? Get bigger injectors?
I'm really a newbe on the injector part of this car so if I do need to upgrade it can anyone please explain to me what I need to do exactly? I really appreciate it guys~~
Thanks

Told you already, get bigger injectors! You're at 100% duty cycle at 6,000 rpm! What do you think would happen if you redlined it a few more times at that rate?
Old 11-28-06, 12:52 AM
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Originally Posted by BoostedFd3s
my mods are: Greddy 3 row fmic, koyo radiator, streetport, downpipe, midpipe, rb duals, apexi intake, greddy pullies, pfc + commander tuned for 12psi...
Take the midpipe off and put your stock cat/ a HF cat on. I am pretty sure your old IC was stock and kept the boost to near stock levels. Now that everything is free flowing, you may be experiencing boost creep. The turbos are in need of a ported WG.
Old 11-28-06, 12:56 AM
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akiratdk, it looks like you are begging for a blown motor.. I would recommend 1st checking to see if you are boost creeping. Once that is settled and if you are still running at 85-100% injector duty to get 1300cc secondary injectors. There is a lot of information in the forum about where to buy and how to install those. BTW, nice pic of the PFC.
Old 11-28-06, 07:22 AM
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oh man.
Old 11-28-06, 08:09 AM
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akiratdk,

What's your A/F ratio (as that is the most important thing)?
Old 11-28-06, 09:23 PM
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Yeah I would definately get a wideband O2 sensor in that thing quick (if you dont already have one) and check out the a/f ratio as stated above. But really in all honesty some of the best advice is to reinstall the stock cat or hf cat. Another thing you may do is adjust the boost setting in the Pfc. pull it down to stock boost levels as well, maybe then at least you won't creep so high... One thing is for sure. get this under control or your next thread is most likely to be entitled "Oh no!!!! I think I just blew my motor!!!!!"
Old 11-28-06, 09:31 PM
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Originally Posted by oo7arkman
"Oh no!!!! I think I just blew my motor!!!!!"
And people wonder why these cars have the reputation they do?
Old 11-29-06, 07:08 AM
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lots of good advice above re a situation that if not remedied immediately will end badly.

the stock turbos, which i gather you have, should not be run above 14 psi as they cavitate and superheat the air causing you to have less oxygen molecules per volume not more as you increase boost. less power more go boom. not good. you need to get your boost down to 14 or a tad less if you expect your turbos and motor to live.

an easy immediate way to do it is as 007arkman suggests, just bolt on the stock cat.

i see your knock number at 80... that's a sign of bad things starting to happen.

glassman's comment about the "reputation" that fd's have is so on the money. if you do your homework i maintain the fd is lethal on the road/track and quite dependable. all it takes is some homework doing reasearch on this site and effort and you can have one of the best performing road cars ever mass produced.

howard coleman
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