O2 sensors, opinions

[Nooby]

not having any problems,
I am going to do spark plugs again in 2 weeks, so I was wondering if there would be any reason to change the 02 sensors as PM

thanks for any advice

also if recommendations are to change them out, aftermarket sensors OK, or stick with dealer's sensors, thanks

02 3.7 4x4
128000 miles

 

[Dave]

I don't think you need to change the 0-2 sensors, because if something was wrong with any of them you would have a MIL and sensor codes.

This is my opinion anyway.

Dave

 

[tjkj2002]

Use NTK(OEM) O2 sensors only,from a online parts place like moparpartsamerica.com it's about $220 or so for all 4 sensors.I'd wait till you throw a code for a bad O2 sensor then replace all 4.

 

[diyman]

For what it's worth....

O2 sensors do fail if they feel like to! They might last 40,50k or ...forever. They seem to be thougher these days.

If You have one, put a scan tool in live data/record mode, then check if O2 voltage varies between 0.15 and 0.9V.
Average should stay at 0.4./0.5V, and voltage should vary many times per second ( otherwise we have a 'lazy'
sensor and in that case, yes, it would be due for a change ). In case, change both.

OEM sensors do come with the connector fitted, thus avoiding some PITA... You'd be better off with the proper tool.

 

[diyman]

Forgot to say. My KJ only has 2 upstream sensors. PCM won't monitor cat's performance.... No CAFE here....

 

[Nooby]

thanks for the quick replay's,

I will not worry about replacing them now, only if I get a code for the 02 sensors, and then I will replace with the OEM sensors

on my wish list is to get a scan tool that can do data/record mode and other features, but still trying to figure out which one would do the most for the best price, feel free to offer recommendations

thanks again for you help

 

[tjkj2002]

.

If You have one, put a scan tool in live data/record mode, then check if O2 voltage varies between 0.15 and 0.9V.
Average should stay at 0.4./0.5V, and voltage should vary many times per second ( otherwise we have a 'lazy'
sensor and in that case, yes, it would be due for a change ). In case, change both.

.

Sort of..............

The pre-cat sensors should switch from near zero to almost 1 volt,and continually switch and never stay at any given voltage.Most scanners will not relay to switching fast enough to gauge a good or bad sensor until you get into the real expensive pro scanners.The post cat sensors should hover right at about .5 volts and rarley switch.

 

[TruLiberty]

my post cat sensor keeps throwing a 0137 code for lack of voltage randomly for the last year...now im getting another code for the engine oil sensor 0522. so i was going to do them both, but not all the O2 sensors just the 1-2 one. bad choice?

 

[waywardtravel]

I installed 2 O2 sensors on a 1978 cj for tuning a carb. It has2 set's of 9 lights one green in the middle and 4 yellow's on either side between .45v and .1volt up and down per light. This made carb tuning and checking easy. The chip that runs the light's is no more than run of the mill. Speed of change has never been an issue and never will be if the sensor makes voltage the light's change....