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Question on -10% fuel on bank 2

  • Thread starter Thread starter ace305
  • Start date Start date Nov 13, 2018
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ace305

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Dec 28, 2011
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#1
  • Nov 13, 2018
  • #1
My log shows -10% fuel on bank 2. I had a misfire on number 5 cylinder. I pulled the plug and it looked dry with carbon deposits. I swapped the COP with number 6. I have no new codes but a slight hesitation when I get on it. I checked compression and I am good. How to I diagnose this issue?

thanks
 

a91what

SendMeUrDataLog
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Apr 6, 2011
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Nov 13, 2018
#2
  • Nov 13, 2018
  • #2
bank may have trended lean with the LTT [long term trim] reset the computer with a reflash. Then watch that bank again.

This leaning on the LTT can cause a lean tip in on acceleration; causes the stumble you are experiencing.
 
A

ace305

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Dec 28, 2011
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#3
  • Nov 13, 2018
  • #3
a91what said:
bank may have trended lean with the LTT [long term trim] reset the computer with a reflash. Then watch that bank again.

This leaning on the LTT can cause a lean tip in on acceleration; causes the stumble you are experiencing.
Click to expand...

awesome thanks. How to reflash? unhook negative? Still puzzled why it did cause the number 5 cylinder miss.
 

a91what

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#4
  • Nov 13, 2018
  • #4
The miss is likely what caused the one bank to trend lean
 
A

ace305

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#5
  • Nov 13, 2018
  • #5
a91what said:
The miss is likely what caused the one bank to trend lean
Click to expand...
thank you. COP? Plug? injector? any way to pinpoint the issue?
 

a91what

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#6
  • Nov 13, 2018
  • #6
You moved the cop if the missfire moves to the new cylinder replace it if it continues plugs. Injector is last resort
 
A

ace305

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#7
  • Nov 20, 2018
  • #7
a91what said:
You moved the cop if the missfire moves to the new cylinder replace it if it continues plugs. Injector is last resort
Click to expand...
I don't have a miss now. How is that possible? How long does it take for the car to recognize the miss?
 

a91what

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#8
  • Nov 20, 2018
  • #8
Likely it will missfire after the plug starts to foul. Give it time
 

wmburns

SN Certified Technician
Aug 14, 2009
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Nov 20, 2018
#9
  • Nov 20, 2018
  • #9
Just wondering. Is the fuel rail pressure sensor intake vacuum reference line connected and leak free?

Do the Long Term Fuel Trim (LTFT's) change between idle and load?
 
Last edited: Nov 20, 2018
A

ace305

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Dec 28, 2011
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#10
  • Nov 20, 2018
  • #10
wmburns said:
Just wondering. Is the fuel rail pressure sensor intake vacuum reference line connected and leak free?

Do the LTFT's change between idle and load?
Click to expand...
LIFTS?
 
A

ace305

Active Member
Dec 28, 2011
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Nov 20, 2018
#11
  • Nov 20, 2018
  • #11
a91what said:
Likely it will missfire after the plug starts to foul. Give it time
Click to expand...
ahhh. makes sense. thank you
 
A

ace305

Active Member
Dec 28, 2011
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Mar 28, 2019
#12
  • Mar 28, 2019
  • #12
a91what said:
bank may have trended lean with the LTT [long term trim] reset the computer with a reflash. Then watch that bank again.

This leaning on the LTT can cause a lean tip in on acceleration; causes the stumble you are experiencing.
Click to expand...
hey, how do i refresh the computer? pull the negative?
 
A

ace305

Active Member
Dec 28, 2011
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Mar 28, 2019
#13
  • Mar 28, 2019
  • #13
wmburns said:
Just wondering. Is the fuel rail pressure sensor intake vacuum reference line connected and leak free?

Do the Long Term Fuel Trim (LTFT's) change between idle and load?
Click to expand...
 
A

ace305

Active Member
Dec 28, 2011
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Mar 28, 2019
#14
  • Mar 28, 2019
  • #14
a
 
A

ace305

Active Member
Dec 28, 2011
171
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28
Mar 28, 2019
#15
  • Mar 28, 2019
  • #15
wmburns said:
Just wondering. Is the fuel rail pressure sensor intake vacuum reference line connected and leak free?

Do the Long Term Fuel Trim (LTFT's) change between idle and load?
Click to expand...
hey, would you mind looking at my log? I can email it to you.
 

OneSick99GT

Active Member
Nov 20, 2018
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Dayton, Ohio
Mar 29, 2019
#16
  • Mar 29, 2019
  • #16
Yes pull the negative for a minute or two and pull out your headlight switch to finish draining any residue power. Re-connect and start. Make sure to drive your stang how you normally drive and make it a longer trip.
 
A

ace305

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Dec 28, 2011
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Mar 29, 2019
#17
  • Mar 29, 2019
  • #17
Onesick99GT said:
Yes pull the negative for a minute or two and pull out your headlight switch to finish draining any residue power. Re-connect and start. Make sure to drive your stang how you normally drive and make it a longer trip.
Click to expand...
thanks, I did the flash and ran a new log same thing.
 
A

ace305

Active Member
Dec 28, 2011
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Mar 29, 2019
#18
  • Mar 29, 2019
  • #18
Longterm Fuel Bank 1 Min: 1.00 Max: 1.01 Avg: 1.00
Longterm Fuel Bank 2 Min: 1.00 Max: 1.16 Avg: 1.02

Compression on all cylinders - 155-160

I have a strong raw gas smell from passenger rear of the car. Only after running the car and hot. Does not smell inside the car, only outside. New fuel pump was installed when engine was. 300 miles on new MMR 900. Has Kenne Bell 2.1 with 60lb Siemans Deka injectors. Original coils 2001. New Plugs

what can i do to run a process of elimination?

Longterm Fuel bank 1 and 2 were fine when i first loaded the tune and did the break in.
 
Last edited: Mar 29, 2019

OneSick99GT

Active Member
Nov 20, 2018
364
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Dayton, Ohio
Mar 30, 2019
#19
  • Mar 30, 2019
  • #19
wmburns said:
Just wondering. Is the fuel rail pressure sensor intake vacuum reference line connected and leak free?

Do the Long Term Fuel Trim (LTFT's) change between idle and load?
Click to expand...

@ace305 Double check this and let burns know.
 
A

ace305

Active Member
Dec 28, 2011
171
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Mar 30, 2019
#20
  • Mar 30, 2019
  • #20
Onesick99GT said:
@ace305 Double check this and let burns know.
Click to expand...
ok, but please let me know what that is. I am unsure what to check.
 
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