ok.i have a 96 jimmy 4.3 liter,and my "SES" light keeps coming on.with the same message. ruuning too rich. the truck runs fine and is getting 17 mpg city.

any ideas?

oh.btw. it comes on at least twice a month

Bad o2 sensor?

EGR valve clogged, multiport injector assembly leaking....did you replace the cat yet?

yes i did.

wouldnt the egr cause an egr fault to come up?

No. The codes are not the problems. They are indicators of the problems. If your EGR valve is working fine, but the inlet is clogged, the computer can give you a rich running code. i've seen it on 4.3's many times. Also, the injectors are notorious for leaking into the intakes.....you need to have it diagnosed.

hmmm..well it does have 197,000 miles on it.

****.that sounds expencive.

um.what about a tuneup?it's over due for a cap/rotor.

Fat chance....

EGR valves arent too expensive, at least it wasnt on my buddy's honda. $150 something and we did it ourselves.

http://rep.racepages.com/parts/racepages/wizard.jsp?year=1996&make=GM&model=JIMM-2{embeddash}DOOR-001&category=All&part=EGR%20Valve&dp=true&showdc=true#top