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Went to do KOER test and my engine revved to 3k all by itself???

  • Thread starter Thread starter Black1987Stang
  • Start date Start date Nov 1, 2005

Black1987Stang

Active Member
Aug 22, 2004
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Jersey Shore
Nov 1, 2005
#1
  • Nov 1, 2005
  • #1
My car was running pretty rough so i pulled the engine off codes with no problems, then i went to try the KOER codes and as soon as i turned my code reader on my engine revved up to like 3k and just stayed there. Ive pulled codes using this code reader hundreds of times before and never done this before. All it does is flash a little light and make a beep in order to send the codes, and after u plug it in to the harness and once ur ready to write down the codes all u need to do is flip a little switch and it will start sending out codes, but instead as soon as i flipped it on, the rpms went to about 3k and stayed there. Anybody have any ideas?


Also the little smilies dont want to seem to work for me? Ill click on one and nothing happens?
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Nov 1, 2005
#2
  • Nov 1, 2005
  • #2
The computer will also perform a number of diagnostic tests when properly instructed -- you must've inadvertantly 'told' it to do so with the reader.
 

srothfuss

Last night I stabbed the same guy 7 times in a row
Oct 17, 2004
1,796
3
0
Woodward Ave.
Nov 1, 2005
#3
  • Nov 1, 2005
  • #3
At the end of KOER the computer can do a cylinder balance test which will raise the idle to around 2,200 and then turn off 1 cylinder at a time to test for various problems...

Maybe your reader was trying to access this part of the program?
 

Black1987Stang

Active Member
Aug 22, 2004
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37
Jersey Shore
Nov 1, 2005
#4
  • Nov 1, 2005
  • #4
srothfuss said:
At the end of KOER the computer can do a cylinder balance test which will raise the idle to around 2,200 and then turn off 1 cylinder at a time to test for various problems...

Maybe your reader was trying to access this part of the program?
Click to expand...

I know what u mean whenever it did the balance test the idle would go to maybe like 1500 rpms max and u could start hearing the cylinders drop for like a half sec. idk maybe my bad maf has something to do with it
 
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