Replacing front O2 sensor (bosch 15310) with O2 sensor socket instructions?

[BoostFrenzy]

-2003 Vibe base automaticCan I do this WITHOUT removing the metal heatshield and from above?

[BoostFrenzy]

nobody's changed their precat o2?

[stoutvibe]

Having replaced my O2 sensor 3 times, I can offer a few tips. You do need to remove the upper heat shield - 2 bolts I believe. Definitely do it from above. It really isn't too bad to get in and out. You will need to use a wrench instead of an O2 socket though, because of the tight clearance to the fire wall. The O2 sensor connection to the engine is extremely difficult to get appart (or was for me at least). There are 2 different locking clips you have to simultaneously lift at the same time, while pulling the two halves appart - wish I had an extra hand. Besides that, you should be good to go. Hopefully yours will last longer than mine - for some reason I have to replace it every winter. I am wondering whether the car is running slightly too rich causing it to burn out. Anyway, good luck!

[BoostFrenzy]

this is a 2003 with 170k miles on it and original sensors/cat, it pops a P0420 for cat inefficiency from time to time and the mpg hasn't been stellar for some time, going to replace the first O2 first and if fuel economy doesn't improve vastly / p0420's go away then the cat will be next :/

[kevera]

It may be your cat,they tend to fail early on these things.

[ToolGuy]

I am going to go with the cat too. If it is not, I doubt your cat will go much further. Usually O2 sensors keep the code and light on, cats can make codes come and go. At least in my experience...

[yotatrix]

I have this problem with the catalytic as well is it because too much LIFT p0420...looks red in color possibly O2 sensors and cat for me

[Mojo72]

While taking off the exhaust manifold's upper heat shield, I managed to shear off the two lower bolts (very rusty) closest to the catalytic converter. Swell! Once I'm finished replacing the O2 sensor, can I get away with using only the two upper bolts to fasten the heat shield? I idled it for about a minute with that configuration and didn't detect any apparant vibration.

[Mojo72]

How much resistance should I be getting when taking off the old O2 sensor? It's on fairly tight and I'm a little hesitant to King Kong it after shearing off the lower 2 upper heat shield bolts. I'm squirted some Liquid Wrench around the base of the sensor and am giving it a few minutes to work.You're right about not having enough clearance between a regular O2 sensor socket and the fire wall. I'm going to try and take it off with a 7/8" open ended wrench and see where that gets me. Of course I won't be able to torque it with the wrench when putting in the new one.

[bassplayaz06]

if you're talking about the sensor just before the cat converter, it's a 22mm nut. and using force is the best thing to do to get it off. that is if it was put on right in the first place.

[Water boy]

WOW21 months between postings.

[bassplayaz06]

i didn't notice when it was posted, i just searched p0420.

[Mojo72]

Thanks for the reply. I ended up using a 7/8" ratchet wrench, but I'm thinking about using a crowfoot socket with torque wrench in the future.