O2 Sensor Time???

[WDP]

I have a 96 XLT, 4.0 SOHC that has had the CEL light on for the last 4 years. It runs great, good mileage and passes the toughest emits in Pa. If it ain't broke. Well the government regulators won't even sniff my tailpipe with the CEL, so it's time to fix the beast. It has 186K miles, orginal upstream O2 sensors(2) and I replaced the single downstream a year ago.(no fix) Codes today read
PO 0153 - bank 2 upstream O2 sensor circuit slow response. and PO 0420 catalist system efficency below threshold (bank 1). Questions?? The two upstreams need replacement, are these calibrated (special) or can I get them at the local parts store? Is the downstream bad again or is the computer looking for a problem caused by the upstream sensors? I don't think the cat (single)is toast because of the emit tests it flys by. Please lay out the order of parts/tests to extinguish the CEL. Thanks for the help.

 

[MaverickDaKid]

When I took mine to Ford they told me if I didn't want to fix it I didn't have to becuase it was just the DPFE or something like that. It wouldn't fail emissions cause of it. So he said just put black electrical tape over where it lights up..... Thats what I call a mechanic lol

 

[BradE.]

Replace the O2's. They can be purchased at just about any autoparts store.

Depending on your states regulations for emissions, your cat could be toast and still pass. Would not suprise me, if you have been driving on bad O2's for 4 years.

 

[WDP]

Replaced the 2 upstream sensors last week, reset the computer and all is well (no CEL). Same power, same mileage so maybe the sensors were just left of center and the computer was a little right. Thanks.

WDP

 

[Nick C.]

get it fixed but if you just want to pass emissions then pull over at a gas station a few miles from where they test it, unhook your battery and then hook it back up it should clear the code for long enough for you to pass.

worked for me

 

[Robb]

Congrats on the fix WDP!

for future reference, your Explorer has the OHV 4.0L

 

[WDP]

Thanks Rob,with all the work I do on the thing, I didn't know it was the OHV engine. Only the 4.0 stands out on the intake and no mention in the owner's manual, a well kept secret. Sorry for being so DUMB!
Resetting the computer won't do with the new read the computer testing, the tester will know the car is in the "learning" mode and will not authorize the sniff test to begin.

WDP