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Need help diagnosing a miss, and one other odd issue.

  • Thread starter Thread starter Fett
  • Start date Start date Sep 13, 2006
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superhuaman

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Nov 8, 2004
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Sep 14, 2006
#21
  • Sep 14, 2006
  • #21
i believe that it would set a 33 code (egr opening not detected) and yes, it would probably pull timing at cruise, or richen mixture, or something...it may or may not ping, but the egr would have to fail to operate several times before the code would set and it would enter limp mode. you might not get a check engine light, either.
 

Fett

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#22
  • Sep 14, 2006
  • #22
Yea, that is the code I had at the time...33.

I am going to take it out in a few minutes, drive it until it gets normal op temp, reset my idle with the IAC unplugged, then drive it some more. I want to see if the "miss" comes back and I want to see how the idle reacts.
 

HISSIN50

"How long does it take to get help in here?
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#23
  • Sep 14, 2006
  • #23
Chris, as I recall, if you're getting a code 33 during KOER retrieval, the puter should have recognized that the EGR function is compromised, and worked around it............
 

Fett

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#24
  • Sep 14, 2006
  • #24
I got that code KOEO, I can't get anything to communicate with the PCM in KOER. I tried with the NGS and a Star Tester, and both would do the same thing when I would try to run a test win KOER. You would hear the engine rev up for a second, then go back to normal idle and the tester would just stare me in the face. The NGS would tell me it couldn't communicate with the PCM with KOER...but it would retrieve memory and hard codes with KOEO.

I took the car out tonight to see how it would react with the EGR vac line plugged. Everything seemed to go fine, it didn't buck, miss, or surge. My idle still does stupid things when the e-fan comes on, or during initial startup. So I took the car out for a while to get it warm, unplugged the IAC and set my idle at 1000rpms. Now when the e-fan comes on the engine doesn't surge like it was doing. When the fan would come on the engine would surge, dropping to 500rpms, then rev up to 1000, then drop to 500, and back and forth...until I reved it up to 2000. Now when the e-fan comes on the idle pretty much stays at 1000. During initial startup, it still surges...now it just does it at higher RPMs.

But I think I figured out my "miss" problem...now I just need to figure out how to eliminate the EGR. Leave it as it is, plugged in but no vac going to it....delete it via "EGR delete plug"....or custom tune. I would like to avoid a custom tune because I don't think I really need it...and spending the money just to remove the EGR would be dumb. I might just leave it as it is now and deal with it later.
 
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superhuaman

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Sep 14, 2006
#25
  • Sep 14, 2006
  • #25
i believe someone mentioned this already, but you cant get KOER codes if there are KOEO codes present. You have to get an "11" or an "111" which is "pass" from the KOEO before running the KOER test.

wow, i just looked at your sig, and your setup's somewhat similar to mine...i may have that idle issue as well, dont know yet.
 
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