Fuel trim at MAX

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BG1988

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having an issue with the fuel trim (positive )it's maxing out and tripping a CEL i.e Long term fuel trim said between 16 and 34


New Throttle body, new MAF, New MAP, new Baro.

also the O2 sensors are a bit funky readings as well..

I can watch sensor 2 slowly rise on sensor #2

mpg dropped to 12.5mpg

idle is ok and stable. ( sometimes misfires, a single misfire) on a cold start esp if it gets into the 30s at night)

no "excessive revving "

no misfire while driving i.e 1,000 1,500 2,000 3,000 rpm range(i don't take it above this. 3k is my max rpm i go to ..)

Enters closed loop (CL)

Cat temp reached 565C so it's dumping fuel typically it's around 360-370C or so under normal conditions


the only code was P0430 AND a pending P0430 code, which is the enabled condition and is part of the "Diagnostic enable condition section"

i.e Predicted catalyst temp was 550C and above for 3600 seconds non-contunuosly..... ready to take it to the junk yard and get a toyota 4runner at lest that shit is reliable :D




I'll try and put the original MAF sensor (a known good one)






edit the other seemed to help but the long term fuel trim was hanging around 10.9


I think there might be an issue with the Fuel pump FRP is 297-312 KPa or 43.51PSI ish

I noted that it instantly goes to 400-410KPa 58.3-59.4 PSI when in "auto stop mode"...
 
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exp500

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What does your scanner report live ? You probably need the VCX Nano and laptop with Factory Service Manual to figure this out.
 
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BG1988

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What does your scanner report live ? You probably need the VCX Nano and laptop with Factory Service Manual to figure this out.
i ran fuel injector cleaner showing 3-5 at idle now(in gear on both banks warmed up) before i was idling at 10.9 in gear.. not misfiring at start up anymore....(single misfire upon startup..)
 

exp500

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Have you put a fuel pressure guage on it to verify? Without the manual handy guess is its low. Or computer and/or relay dropping out. Pretty good troubleshooting chain in the factory man.
 
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BG1988

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Have you put a fuel pressure guage on it to verify? Without the manual handy guess is its low. Or computer and/or relay dropping out. Pretty good troubleshooting chain in the factory man.
everyone told me it was normal. 300KPA = 43 psi
 

exp500

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low side of making it. And thats the standalone guage correct? Meaning you verified your electronic toy is accurate? And are you in Canadia? whassup with your numbers?
 
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BG1988

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Vacuum leak.
it has all ready been checked for a vacuum leak.. and it's not misfiring on startup...

the computer is calibrating the fuel trims


it runs a lot of better now then it did before I just need to get a AFM disabling device and auto stop disabling device, so I can have my EVT gears with v8 100% engine...


you want to know I know it's fixed the calculated Temp of the Catalytic converter is lower 420-450C instead of the 530-560C that must mean it's not dumping fuel into the converter"

this is at 2,000 RPM 50mph M4


430C is the normal working temperature for a Catalytic converter
 
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swathdiver

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it has all ready been checked for a vacuum leak.. and it's not misfiring on startup...

the computer is calibrating the fuel trims


it runs a lot of better now then it did before I just need to get a AFM disabling device and auto stop disabling device, so I can have my EVT gears with v8 100% engine...


you want to know I know it's fixed the calculated Temp of the Catalytic converter is lower 420-450C instead of the 530-560C that must mean it's not dumping fuel into the converter"

this is at 2,000 RPM 50mph M4


430C is the normal working temperature for a Catalytic converter

I remember now, has the Fuel Trims been reset along with the Alcohol Content with a tankful of E10?
 

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