ECM EGR Test Concept
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From: Derry nh
ECM EGR Test Concept
Anyone know how the ECM performs its EGR test? My '91 had its EGR valve and solenoid removed and used to expectedly but harmlessly throw EGR code 32 and light the SES. Since my injectors were changed, that doesn't happen any more and I'm having an issue with reduced mileage (down 30%) so trying to see if my lack of EGR SES might give some clues to my mileage issues.
Thought I remember being told the ECM checks that when the EGR opens there is a corresponding change detected in the O2 sensor. If the check now passes (no code or SES) but used to fail, then maybe the O2 sensor is bad? Are there more than one O2 sensors in a '91? THe ECM O2 test passes though, so I'm really confused about what's going on.
Thought I remember being told the ECM checks that when the EGR opens there is a corresponding change detected in the O2 sensor. If the check now passes (no code or SES) but used to fail, then maybe the O2 sensor is bad? Are there more than one O2 sensors in a '91? THe ECM O2 test passes though, so I'm really confused about what's going on.
