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code 31 at wot?

  • Thread starter Thread starter No.11
  • Start date Start date Sep 24, 2011

No.11

10 Year Member
Oct 13, 2009
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Sep 24, 2011
#1
  • Sep 24, 2011
  • #1
ever since I properly grounded the injector harness, and properly set the TPS voltage, I stopped getting codes 31 and 63. I used to get it while driving intermittently.

I've gone wot twice since I fixed those things, and both times I've gotten the check engine light. I read the codes and got only a code 31. so... this doesn't make sense. isn't the EGR supposed to shut off at wot? why is this code coming up only at wot?
 

jrichker

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#2
  • Sep 24, 2011
  • #2
Possible TPS problem - TPS not reaching full voltage at WOT. Look in the Techinical Thread Sticky for checking/setting the TPS.
 

No.11

10 Year Member
Oct 13, 2009
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Sep 25, 2011
#3
  • Sep 25, 2011
  • #3
thanks jrichker. wouldnt that throw a code 63? and I did set the TPS to .93 after having to notch the holes. maybe a new TPS is in order? I do have a $90 cjpony gift card. getting some swaybar endlinks, bushings, guess I'll throw in a new TPS as well.
 

Mustang5L5

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Sep 25, 2011
#4
  • Sep 25, 2011
  • #4
Well what he's saying the that the TPS is having trouble reaching WOT voltage to signal to the EEC that the car is at WOT.


Basically, find your idle voltage reading (0.5 - 1.1v) and then add 2.71 to that number. Now, have someone press the gas pedal to the floor while you watch the voltage. Verify that the voltage increases above the number you just added up. If it does, your TPS is fine and you need to look elsewhere.
 

No.11

10 Year Member
Oct 13, 2009
614
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Sep 25, 2011
#5
  • Sep 25, 2011
  • #5
ahhh ok will try that today mike. question though. ive been told that pressing the gas pedal on fuel injected cars while the engine is not running will still inject fuel into the engine and might cause it to flood... is this just an old wives tale?
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,154
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Massachusetts
Sep 25, 2011
#6
  • Sep 25, 2011
  • #6
No it won't. In fact, holding the gas pedal to the floor while cranking turns off the injectors so you are able to start a flooded engine...this trick comes in handy when you have ECT issues.
 

No.11

10 Year Member
Oct 13, 2009
614
10
48
Los Angeles
Sep 25, 2011
#7
  • Sep 25, 2011
  • #7
ahhh I see! good to know thanks!
 

No.11

10 Year Member
Oct 13, 2009
614
10
48
Los Angeles
Sep 25, 2011
#8
  • Sep 25, 2011
  • #8
did the voltage check again, .93 and then got 4.61 at wot... So am I ok then as long as the voltage goes over the +2.71?
 

No.11

10 Year Member
Oct 13, 2009
614
10
48
Los Angeles
Sep 25, 2011
#9
  • Sep 25, 2011
  • #9
also something im not sure about. I have all the smog stuff deleted, back of heads plugged, no coolant running through EGR spacer (gt40 intake didn't have provision for it). does the EGR function without all of that or should I just get rid of it?
 
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