'97 Tahoe 5.7L running rich

hchristiansen

I recently changed the fuel pump in my '97 Tahoe and the
next day the SES light came on. I scanned the trouble
codes from the VCM and it turns out that both banks are
running rich. Chilton manual confirms that the codes
indicate a rich mixture condition.

The problem is that the Chilton manual does not give me
any idea of how to correct the problem.

Anybody seen this and what did you do fix it?

Thanks, Howard

99tahoe1

Hey ya i did the same thing and now i have the same problem also if you have gotten any ideas let please let me know thanks a lot

jjipson

same here, truck died, replaced pump, truck ran(sort of) replaced airflow sensor, ran good, but rich, ses lite on, scanned,6 codes, O2 sensor,insuficent catalyst, R+L bank, rich-R+L bank. changed #2-L O2 sensor, ses still on, still rich. don't know why! :mad: