Help with long term fuel trim bank 1

NewOrleans-YAT

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ok, so after looking at the log, the fuel trim evens out under load. the separation starts as the motor RPMs fall.

At 3098 RPM the fuel trim is 1 to 1
At 803 RPMs the fuel trim is 1 to 1.19

also the car runs awesome by the way.

I checked compression on all cylinders 155-160
COPs seem to be ok
throwing code P0443
new plugs
new 60lbs Deka injectors
300 Miles on new MMR 900 build
Kenne Bell 2.1

i have no clue what to do
 

Sluggie24

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If a fuel trim is high enough to set a code then you either have a vacuum leak, an exhaust leak, an injector problem or an O2 sensor problem. At least those are the problems that are most common.
 

Sluggie24

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Fuel trims are always trying to reach 0. If it's a + fuel trim the computer is adding extra fuel to get to 0. If it's a - fuel trim the computer is subtracting fuel to get to 0.

Since your one bank is + high that bank is lean, or at least the computer thinks its lean.
 

NewOrleans-YAT

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Fuel trims are always trying to reach 0. If it's a + fuel trim the computer is adding extra fuel to get to 0. If it's a - fuel trim the computer is subtracting fuel to get to 0.

Since your one bank is + high that bank is lean, or at least the computer thinks its lean.
thank you

ok makes sense. Its only high at idle. it seems to be normal on a load. so its lean at idle but normal on a load?
 

NewOrleans-YAT

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Look for a vacuum or exhaust leak first
I am getting this code

Could it be related? Also what should i change first to remedy this code. Also the fuel tank grommet is torn and leaking. I read that this can affect the EVAP system as well. I am changing the grommet next

P0443 - EVAP Control System Canister Purge Valve Circuit Malfunction The PCM monitors the state of the EVAP canister purge valve circuit output driver. The test fails when the signal moves outside the minimum or maximum limit for the commanded state. VPWR circuit open
EVAP canister purge valve circuit shorted to GND
Damaged EVAP canister purge valve
EVAP canister purge valve circuit open
EVAP canister purge valve circuit shorted to VPWR
Damaged PCM
To verify normal function, monitor the EVAP canister purge valve signal PID EVAPPDC (or EVMV for electronic valve) and the signal voltage (PCM control side). With the valve closed, EVAPPDC will indicate 0% duty cycle (0 mA for EVMV) and the voltage approximately equal to battery voltage. When the valve is commanded fully open, EVAPPDC will indicate 100% duty cycle (1000 mA for EVMV) and a voltage drop of 3 volts minimum is normal. Output test mode may be used to switch output ON/OFF to verify function.
 
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Sluggie24

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If you already know that the grommet is damaged then replace it. Clear the codes. Drive/run the car and see which codes if any return. Make sure to check the fuel neck under the plastic cover they zip tie around it. They like to rot out in there and get holes. If yours has holes starting, or looks really rotted/thin replace the neck as well. You will have to cut the zip ties and remove the cover to see it properly.
 

NewOrleans-YAT

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If you already know that the grommet is damaged then replace it. Clear the codes. Drive/run the car and see which codes if any return. Make sure to check the fuel neck under the plastic cover they zip tie around it. They like to rot out in there and get holes. If yours has holes starting, or looks really rotted/thin replace the neck as well. You will have to cut the zip ties and remove the cover to see it properly.
on it. thanks i will report back
 

NewOrleans-YAT

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i c makes sense.

yea fix the grommet first and see what you get
ok thanks.

on another issue.

On cold start if fires immediately, after reving the engine and gets to idle it will struggle to stay ideling, not every time but 3 out of 5 times. Then on a warm engine start it struggles to start.

what is the easiest way to drain the tank? its 3/4 full.
 

decipha

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the startup issues and all are just due to the tune not being dialed in yet I wouldn't be concerned with it just let your tuner know

as for draining the tank, you can disconnect the feed line at the fuel filter and put it in a bucket or gas cans. You'll have to jump off the fuel pump wire at the FPDM to keep it running until you drain the tank.
 

NewOrleans-YAT

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the startup issues and all are just due to the tune not being dialed in yet I wouldn't be concerned with it just let your tuner know

as for draining the tank, you can disconnect the feed line at the fuel filter and put it in a bucket or gas cans. You'll have to jump off the fuel pump wire at the FPDM to keep it running until you drain the tank.
awesome thanks
 

NewOrleans-YAT

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the startup issues and all are just due to the tune not being dialed in yet I wouldn't be concerned with it just let your tuner know

as for draining the tank, you can disconnect the feed line at the fuel filter and put it in a bucket or gas cans. You'll have to jump off the fuel pump wire at the FPDM to keep it running until you drain the tank.
any idea why bank 2 runs 15% higher at idle but runs the same as bank 1 at higher rpms? at 4500rpms both run 1 to 1. at 2500 it runs 1 to 1.15

IMG-0286.png

IMG-0288.png
 

decipha

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usually its just an air leak or exhaust leak. I've also seen cam timing being off cause it. I wouldn't be too concerned with it considering both the trims come together up top where it really matters and you said it runs awesome.
 

NewOrleans-YAT

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usually its just an air leak or exhaust leak. I've also seen cam timing being off cause it. I wouldn't be too concerned with it considering both the trims come together up top where it really matters and you said it runs awesome.
thanks. when i set the timing, i rotated the engine 15 times to make sure there has no valve piston contact. Funny thing i that it did not start this issue untill 100 miles after first start. I checked all my logs from the first one.

how can i determine if its a vacuum leak? I installed the Kenne Bell myself and I'm no pro. There could defiantly be a leak. just not sure how to find it. Should I be looking for an issue on Bank 2? When i first found the issue #5 cylinder fouled and threw a code for #5 misfire. I changed the boot and spring for the COP and moved it to #8. it never came back. But bank 2 still has the issue.


thanks for all your help. i can paypall you $20 for your advise
 
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decipha

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no paypal needed lol

best way to find an air leak is to smoke it. Seal off the maf with a coupler with a bung and hook up a smoker/fogger. You will easily find where there are leaks.

If your in kenner there is Woodys Automotive on bainbridge right there by the airport. Mr.Gary there has a smoker and can prob have you in and out in a few minutes. I dont think it would be any more than $20.
 

NewOrleans-YAT

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the startup issues and all are just due to the tune not being dialed in yet I wouldn't be concerned with it just let your tuner know

as for draining the tank, you can disconnect the feed line at the fuel filter and put it in a bucket or gas cans. You'll have to jump off the fuel pump wire at the FPDM to keep it running until you drain the tank.
hey, could give me some directions on jumping the fuel pump at the FPDM? I have been searching the net but can't find any good info.
 

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