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Computer code 34..help

  • Thread starter Thread starter latham83
  • Start date Start date Aug 29, 2004

latham83

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Jul 24, 2003
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Aug 29, 2004
#1
  • Aug 29, 2004
  • #1
Hey guys...i was doing some tests on stuff and my car has been pulling code 34 with the engine off key on test for a long time...and today i did the engine on key on test and it still pulled it...I looked it up in the book, and there are 4 different things it could be?? like 3 of them were something about the PFE sensor and its voltage, and the the other one was EGR not closing or opening properly....so whats going on? anyone ever have this code...i have 1990 5.0..
theres stuff in my sig there...
what the hell is the PFE sensor and where is it at?
and how can i test or find out which code 34 it is?
 

HISSIN50

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Aug 30, 2004
#2
  • Aug 30, 2004
  • #2
hey bud. do a search for Jrichker post on code 34. he has a nice write up. i would do it for ya, but i cant seem to find the search button (along with some others. hmmmm).
good luck.
 

jrichker

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#3
  • Aug 30, 2004
  • #3
Code 34 EGR voltage above closed limit - Failed sensor, bad or missing signal ground, carbon between EGR pintle valve and seat holding the valve off its seat. Remove the EGR valve and clean it with carbon remover. Prior to re-installing see if you can blow air through the EGR valve by mouth. If you can, replace the EGR valve ($85-$95).

If the blow by test passes, and you have replaced the sensor, then you have electrical ground problems. Check the resistance between the black/white wire on the MAP/BARO sensor and then the black/white wire on the EGR and the same wire on the TPS. It should be less than 1 ohm. Next check the resistance between the black/white wire and the negative battery post. It should be less than 1 ohm.
 

latham83

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Jul 24, 2003
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Aug 30, 2004
#4
  • Aug 30, 2004
  • #4
ok but what are they other 3 code 34's that are listed in my chiltons manual?? they say about the PFE sensor? whats that?
i did buy a new egr sensor for it awhile ago, and that did not get rid of the code pull...if any of those wires are above 1 ohm, is that the problem? what do i do then?
and personally what do you usually see the problem is that this code is pulled?
 
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