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very high air/fuel ratio...sputtering...bad gas?

  • Thread starter Thread starter mamatried
  • Start date Start date Aug 19, 2011
M

mamatried

New Member
Sep 28, 2004
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Kentucky
Aug 19, 2011
#1
  • Aug 19, 2011
  • #1
i finally got my wideband hooked up and my car at idle is running at 20:1 afr which is way high. even when i rev up on the engine the ratio only drops to about 16:1. I've adjusted my fuel pressure from 40 to 30 psi and it had no affect! i have 30# injectors too. it has new plugs, coil, rotor and cap. i know i'm getting fire but i'm running way too lean. i know its has the same tank of gas in it for a couple years could this be causing it to miss and have such a lean mixture??
 

TenorPlayinGuy

Founding Member
Aug 3, 2001
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Canyon Country, Ca
hometown.aol.com
Aug 20, 2011
#2
  • Aug 20, 2011
  • #2
What else has been done to the car? 30lb injectors are quite a bit for no other modifications. We need more details to help you troubleshoot this lean condition.
 

FastDriver

I was uncomfortably high & wearing a helmet
SN Certified Technician
Sep 5, 2001
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Vass, NC
Aug 20, 2011
#3
  • Aug 20, 2011
  • #3
The typical response to a lean condition is to increase fuel pressure, not lower it. Still, with 30s you shouldn't have had the issue at 40 psi in the first place. Is your MAF calibrated to the 30lbs injectors? Have you replaced the fuel filter recently? Did you connect it backwards? Is the wideband getting hot enough to take an accurate reading? Are you measuring the pressure at idle? When you plug the vacuum into fuel pressure regulator, how much does it drop?
 
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