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2001 s10 blazer secondary air pump bypass

3K views 1 reply 2 participants last post by  frdboy 
#1 ·
Bypassed pump with a light to complete circuit on both wiring plug work about two day then engine light comes back on. Any help.
 
#2 ·
You can't fool it that way, the PCM monitors the O2 voltages to diagnose AIR system. During the AIR test, PCM activates the AIR pump during closed-loop operation. When AIR system is activated, PCM monitors the HO2S voltages and short term fuel trim values for both banks of the engine. If AIR system is operating properly, O2 voltages will go low and short term fuel trim will go high.

I don't think there is a way to fool it, maybe could have someone with EFI live or HP tuners turn that sys. and codes off if they support that PCM.
 
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