Hey folks!

I recently had a CEL that stated "slow 02 response" or slow 02 heat. Something like that. I was wondering, because it tripped an 02 specific do y'all think I should think about replacing at least the 2 front or the 2 back ones? I think the back ones are fine because the CEL said nothing about emissions, just sensor operation. Is it the fore cat or aft cat sensors that go bad?

Thanks!

 

if you have over 100k i would just go ahead and change the front ones.dont worry about the rears for now. i changed mine and got 2 more mpg. those sensers are important.

 

Hey keith, well my truck only has 20,000 on it but the sensors and emissions equipment are 10 going on 11 years old and I'm just betting the sensors are tired.

So the front two are the important ones right? And more prone to causing bad mileage/failure? Rear ones rarely go out, they just trip if they sense the CATS are bad right?

 

o yea i remember you. i was asking how you found a 97 with 20k. i was jealous lol. some guys in here have over 200k and never changed the rear ones and still get decent mileage. the front ones are important if those fail it can help ruin the cats. they usually last 100k or so....but your truck is 10 years old. what kind of miles per gallon are u getting??

 

Miles per gallon aren't super duper good but I remember about 1 month ago it was around 13-14MPH city. I don't highway drive alot so I couldn't tell ya. I drive 16 miles total 5 days a week to work and back 8 miles 1 way. Do ya think it would be beneficial to replace all 4??? Or just do front two and see what that gets me?

 

if your getting 13-14 city thats not bad. if you plan on keeping the truck for awhile i would just go ahead and replace the front 2. unhook the battery, both cables. positive cable first when reconnecting. maybye it didnt store the code and light might go out.

 

Don't waste your money throwing parts at it.

Ignore the downstreams unless you have a fault code that points to them. In that case, you'd need to follow the proper diagnostic to determine if the fault is due to the sensor(s) or something else.

As for the upstreams, a lot depends on what your actual fault code was. There are several codes that would seem to implicate the O2 sensors, but the problem is elsewhere.

Again, a PROPER diagnosis is essential to keep from wasting your money.

Steve

 

Alright guys thanks, my mechanic cleared the light, hasn't come back on so hopefully all will be alright.