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Old 03-11-2018, 09:16 AM
VRSENVL VRSENVL is offline
 
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Default Unplugged Oxygen Sensor Rationale

I have a recently bought '88 Carrera that underwent a PPI during the buying process. The inspection revealed a couple minor things but one of the items was an unplugged O2 sensor. He had no idea why someone might unplug it, but the car is running a Steve Wong chip (if that matters ). Any rationale why you would unplug it?
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Old 03-11-2018, 02:49 PM
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Not with EFI. Old trick was to unplug it on CIS systems. 02 was more for emissions than balance.
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Old 03-12-2018, 09:31 AM
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I would think with a 3.2 EFI engine it would run worse w/o the O2 sensor attached. Maybe the sensor was bad and they were too cheap to replace it?

Heck I had an O2 bung installed on my heat exchangers to better dial in my carb'd 2.7 when I get it installed. I can also use it when/if I go EFI in the future
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Old 03-12-2018, 09:42 AM
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Car should run rich. Do you have a history of the motor? Makes sense to me if chip is written for specific mods and ultimate power is the goal over full range operation. Talk to Steve Wong.
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Old 03-12-2018, 09:57 AM
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This ^^Not a tuning expert but from my limited knowledge, Wong probably programmed the chip to run off of his tables/maps based on dyno results as opposed to relying on data from the O2 sensor.(i.e. open loop vs. closed loop) By unplugging the O2 sensor, the computer relies on the maps that have been programmed in and designed for performance as opposed to emissions. None of my racecars with Behe made chips use O2 sensors. Probably runs a little rough until warmed up?
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Old 03-12-2018, 07:42 PM
VRSENVL VRSENVL is offline
 
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Quote:
Originally Posted by cmartin View Post
Car should run rich. Do you have a history of the motor? Makes sense to me if chip is written for specific mods and ultimate power is the goal over full range operation. Talk to Steve Wong.
Motor should be completely OG based on history. No additional mods.
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Old 03-12-2018, 07:43 PM
VRSENVL VRSENVL is offline
 
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Quote:
Originally Posted by TurboPooch View Post
This ^^Not a tuning expert but from my limited knowledge, Wong probably programmed the chip to run off of his tables/maps based on dyno results as opposed to relying on data from the O2 sensor.(i.e. open loop vs. closed loop) By unplugging the O2 sensor, the computer relies on the maps that have been programmed in and designed for performance as opposed to emissions. None of my racecars with Behe made chips use O2 sensors. Probably runs a little rough until warmed up?
This makes sense. Car is a little rough at start. Iíll have to do some testing this weekend to see how it is with/without the sensor.
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