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-   -   Injectors 100% duty cycle stock power? (http://www.njfboa.org/forums/showthread.php?t=66375)

jts98z28 09-01-2015 11:59 PM

Injectors 100% duty cycle stock power?
 
hey, my friend has a bone stock 2000 formula and recently had p0171 & p0174 come up (lean bank 1 &2), so i was checking it out today and he had a huge tear in his PCV valve hose that connects to the intake so we fixed that and so far his codes havent come back, but i did take his car for a drive before i swapped out the hose with my hptuners to log a drive with it and noticed that his cars LTFTs are maxed out at WOT and his injector duty cycle is at 105% and he is lean, so i am wondering if i am right in thinking the injectors are either clogged up or on their way out? as far as i know they are original as the car only has 40K miles, and it literally has a K&N filter, and corsa muffler (not even a catback) so it is far from being too much power for the injectors
Any input is greatly appreciated
thanks
jake

sweetbmxrider 09-02-2015 07:30 AM

What was the stft? Chances are there is still a vacuum leak and the injectors are trying to increase their fuel delivery to bring the afr down.

BonzoHansen 09-02-2015 07:42 AM

did you check again after the fix?

FlyingDutchman 09-02-2015 07:48 AM

Wait, you had a massive vacuum leak and logged before you fixed it? What you're seeing with HP Tuners would make sense as you're pulling a lot of unmetered air in which the O2s are seeing and reporting a lean condition which the PCM is trying to fix by dumping fuel in (hence maxed LTFT and injector duty cycle >100% at WOT). It will take time to relearn and readjust the LTFTs unless you reset them. Like SBX said, look at what the STFT/LTFT are doing now that you fixed it.

sweetbmxrider 09-02-2015 09:07 AM

Oh it was before? Ya, the vacuum leak means the motor will add more fuel to bring the fuel trims back down.

xrelapse13 09-02-2015 10:22 AM

If you took it for a drive before you fixed it like you said, that makes 100% sense. You're pulling air in post MAF that's not being metered. O2 sensors will read the lean condition and trim to add fuel to correct a perceived lean condition.

Reset the Fuel trims post fix, and re log. If still unnaturally high, check fuel filter.

jts98z28 09-04-2015 12:12 AM

wow thanks for all the responses, i originally took it for a drive to log it to see how everything is running cause he recently bought it, and noticed the vacuum leak afterward and by the time i went to the parts store and fixed it he had to go to work so i wasnt able to reset the fuel trims or log it again, i just wasnt sure if the vacuum leak could throw it off that much since it completely maxed out the ltfts amd its a 15 year old car at this point so i wasnt sure if the injectors had much life left in them, but so far he has had no problems so it seems like the leak was all that was wrong with it so thats a plus, thanks a lot for all the help it is much appreciated!


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