How do you know they checked OK
What tests did you do for the EGR system, do you know what the ECM needs to know when it comes to diagnosing a problem with the EGR system , my guess would be no.
The same applies to the O2 sensor, what tests did you do.
If the codes were set then there is a problem with both of those systems, you can search the net on how to reset the light but it will be back on within a few days with the same 2 codes
check engine light on. Set 2 codes egr and o2. Both check out o.k. is
> there a reset switch for emission system or how to clear codes.
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