error codes p1153 and p0153

[tuxhoe]

Service engine light came on,on a 96 blazer, and I was able to pull these codes. I have replaced the oxygen sensors if front of and directly behind the cat converter. Reset the computer and the engine light comes back on. I have noticed no change in the vehicles performance in fact my mileage went up after the engine light went on. I see 2 more o2 sensors, one on each header prior to cat converter. Do any of these need to be replaced? Am I Missing something easy? The wiring leading to the o2 sensor pigtail appeared intact when I changed them. Any ideas would be greatly appreciated.

[braves100]

I am having the same problem (same codes) with my 96 Blazer. Did you ever get it resolved? Which o2 sensors did you finally replace?

[SpitAndDirt]

Your mileage probably went up because the computer went into "limp home" mode where it uses a preprogrammed set of fuel maps, instead of relying on the O2 sensors for exhaust feedback. If you have those codes I would recommend replacing the Upstream sensors as a pair and then reset the computer. Start with that and see if anything improves. -Chris

[BlazerLT]

Through those codes you have a bad passenger side manifold O2 sensor.

Replace, reset your computer by removing the negative battery cable for 5 minutes and enjoy your truck back to normal.