What causes rich condition?
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My car is a '99 Trans Am M6, stock except for an exhaust cutout.
I had it on the dyno for the first time on Saturday, and it was off the charts rich. A TechII scan revealed that it's at about 9:1 A/F. O2s and MAF both seem to be fine.
What could be causing the car to be so rich on the stock tune? I'm afraid to tune it much leaner in case something else is causing it.
I had it on the dyno for the first time on Saturday, and it was off the charts rich. A TechII scan revealed that it's at about 9:1 A/F. O2s and MAF both seem to be fine.
What could be causing the car to be so rich on the stock tune? I'm afraid to tune it much leaner in case something else is causing it.
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Stock tune is known to be on the rich side to begin with but not THAT rich. Some logging with AutoTAP or HPTuners would be very helpful in this case. I'm not sure if an exhaust leak would cause you to run rich or lean but it may be something to check.
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Exhaust leak will cause rich condition. Especially if it close to the 02 sensors. The exhaust will be pulling in outside air and tricking the computer into thinking its running lean. the computer will then add more fuel to offset this condition.