Topic: 02 sensor

[minespath]

i got a code 12 and 21 on my tj , could a 02sensor efect the pick up on a  97 4cyl /auto?

[sharpxmen]

rule of thumb: if you get an O2 sensor code replace it, won't fix itself
you can reset the computer but if it comes back then swap it for a new one (unless the cable is unplugged, so you might want to check that first)

i'm not sure what you're asking though ("pick up"), if the question is will it affect the way it runs then yes, it will.

[dwtaylorpdx]

Only 1 out of ten times I've gotten a 02 code has it been the actual sensor, cracked exhaust manifold, bad injector, bad intake manifold gasket, hose came off that runs the vacuum disconnect on the axle.... and thats just my jeep, dont even get me started on the BMW's I own.

Always start with the basics, is the air system tight and is ther fuel system workig then head down the ECU/Sensor Rabbit hole.... 

I have a set of spare O2 sensors in my tool box now....

Dave

[sharpxmen]

I have a set of spare O2 sensors in my tool box now....

"a set"
I thought you have a YJ

[dwtaylorpdx]

It took me more than once to figure out the code was wrong...  Also I have a xtra sensor for the Beemer as well.. 

Dave

[sharpxmen]

there's more than 1 O2 sensor code, there are rich/lean correction factor codes (51/52) and 21 (which he asked about) which is related to the way the O2 sensor operates (voltage out of spec, response time, heating element - all monitored by the pcm and fairly straight forward if there are no electrical issues with the o2 sensor wires) and for this case a vacuum leak is really not related (cracked exhaust manifold maybe).

51 or 52 by common sense would make you think that could be triggered by a vac-leak but honestly i think you might be mixing some of your other vehicles with the Jeep - I don't really see how a bad intake manifold gasket or vac line to your axle (a vac leak in general) would result in an O2 code, our Jeeps use a MAP sensor, could happen with a MAF sensor but that's not our case, you have a vac leak your idle goes high.

[dwtaylorpdx]

Naw, the jeep it definately was the intake gasket one time. I had just had it off, the new gasket was a multi piece, (Avoid these)
I replaced it with a fel-pro and the problem went away. It was setting the code at cruise. The idle was up about 150 RPM.

When I put my Warn axles hub conversion in the plug the shop put in fell out. Similar deal, cruising down the highway
and get a check engine light... Lean on the O2...

I know we've chatted about my rigs ECU in the past, something about the Late 94 is weird... I suspect voodoo...
I hope to have the cash this month to order a new ECU and see if that settles some of the weirdness out...

I want a second one anyway to gut for a hidden standalone...

Dave