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Checked Codes tonight help me decipher please

  • Thread starter Thread starter cheese_05_70
  • Start date Start date Oct 14, 2009
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cheese_05_70

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Oct 19, 2009
#21
  • Oct 19, 2009
  • #21
I switched O2 sensors still a code 91 all other codes are gone didnt have it warmed up. I'm pretty sure its just an intake leak on number 5. Plug wasnt wet looked dark brown but thats because it running rich. Compression test was 160 that what the others are too. Did another cylinder balance test tonight and it passed code 9. It is getting worse to drive and the sound/leak is getting louder so it kinda goes together.
Thanks for all the help from everyone

Also lil joe how do you like that systemmax intake? any power #'s?
 

liljoe07

5 Year Member
Feb 18, 2009
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Oct 19, 2009
#22
  • Oct 19, 2009
  • #22
Well, this thing is still on the engine stand. But, the intake was stolen out of my garage a few weeks back. But I got another one coming. So now Ill have about $950 in one intake......LOL.

do you have a fuel psi gauge on the car?
 

liljoe07

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Feb 18, 2009
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Cartersville,Ga
Oct 19, 2009
#23
  • Oct 19, 2009
  • #23
Two things to check.

Make sure the O2 has power and ground. Use the two white wires on the sensor and test with a volt meter. Black wire on the 02 goes to the ECM. I would make sure its switching. .2-.9v is good. Check it at the ECM pin. If thats good, get that whistle fixed.
 
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cheese_05_70

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Oct 20, 2009
#24
  • Oct 20, 2009
  • #24
wow that sucks ok
i will check that tonight as long as i got voltage at the computer my power wire and ground is good right. or do you want me to check that to and make sure im getting the right amount of power? thanks
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Oct 20, 2009
#25
  • Oct 20, 2009
  • #25
cheese_05_70 said:
wow that sucks ok
i will check that tonight as long as i got voltage at the computer my power wire and ground is good right. or do you want me to check that to and make sure im getting the right amount of power? thanks
Click to expand...

Check the actual signal, preferrably at the EEC.

You want to see good amplitude and frequency (the reading ranging from 0.1 to 0.9 V and doing so quickly). As sensors age, they lose both amp and freq.
 
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cheese_05_70

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Oct 24, 2009
#26
  • Oct 24, 2009
  • #26
Checked O2 sensors

checked voltage at computer nothing on pin 43. pin 29 got voltage all over the place never stopped changing which is good but nothing on pin 43 where do i go from here?
 
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cheese_05_70

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Oct 25, 2009
#27
  • Oct 25, 2009
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Anyone? Where the O2 harness plugs into the main harness is there supposed to be two 12v source one for each O2? Or is there just one and it split in the O2 harness? Thanks
 

liljoe07

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Feb 18, 2009
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Oct 25, 2009
#28
  • Oct 25, 2009
  • #28
cheese_05_70 said:
Anyone? Where the O2 harness plugs into the main harness is there supposed to be two 12v source one for each O2? Or is there just one and it split in the O2 harness? Thanks
Click to expand...

Only the 02 signal wires are seperate. The Power and Ground come form one PIN then split off somewhere in the Harness.

Did you verify the 02 was actually getting power? Easiest way is just to use a volt meter. The two white wires are the Power and Ground. Turn Key on. Put one Meter lead on the white wire and the Negative lead on the other white wire. Should register 12v on the meter. If not then you need to trace the power and ground wires back into the Harness.
 
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cheese_05_70

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Oct 25, 2009
#29
  • Oct 25, 2009
  • #29
I just measured and everything is working correctly I think. Im preatty sure it is from my intake leak. My right O2 has all kinds of numbers between 0.2-0.9v My left one sits on 0.00-0.02 but you blip the throttle and it is all over the place just like the right but at idle or steady throttle it is right at 0.00-0.02 I thinks it is from air entering the syetm correct?

Thanks you have been great help
 

liljoe07

5 Year Member
Feb 18, 2009
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Cartersville,Ga
Oct 25, 2009
#30
  • Oct 25, 2009
  • #30
Yeah, Id get the intake leak fixed first.

You may also wanna try and ohm out the 02 sensor wire to PIN 43. Just to make sure its ok.
Ohm reading should be low. 0-5ohms is fine.
 
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