c/e light

2000 4.8 4 codes two are down stream o2 both banks. the oter code was p1155 does any one know this code. thanks

Bank2 Sensor 1 is reading lean (O2 Sensor).

//2000CAYukon

thank you . do you have any ideas why i would be lean ? i just tuned it up and replaced fule pump. only had 50 psi at pump. now i have 60 to 65.

A vacuum leak, clogged injector(s), exhaust leak or a misfire on bank 2 (passenger side). If you replaced plugs or plug wires on that side, double check everything.

//2000CAYukon

Thanks Ill Check And Let You Know What I Find. Ireally Am Glad You Replied Thanks

2000 4.8 4 codes two are down stream o2 both banks. the oter code was p1155 does any one know this code. thanks

when the down steam sensors DTC,,, this is the cats , or the O2 sensors are bad...
O2 sensors have a life of 100,000mi....when you go over 140,ooomi you usually get cat failure at some point..depends on how well the engine was maintaned/operated...

the PO155 DTC is usually the O2 sensor wiring....as the heater of the O2 is not correct...and also a bad fuse...the p1155 does not compute...

could both o2 s be bad ? i dont know how well it was taken care of. i checked for vac leaks . did knot find any. could fule press reg be the problem.thanks.