Bruunz

Hi,

A quick one. As the title suggests, i will be replacing my CAT and both O2 sensors and would like to know the best way to access this?

Should i jack up front only, rear only or the whole car?

Thanks,

B

Hfreak

Whole car for best access or just the passenger side if you have a USDM version.

Bruunz

Thanks for the tip. Hopefully will get it done this weekend.

Anything else i need to be wary about?

spdracerut

Nuts are going to be stuck. Use PB blaster a few times ahead of time to help loosen them. But expect on needing new hardware. Best if you have an impact wrench to break the nuts loose.

Chuck S

Good luck. This may not be a "Saturday morning project."

I soaked the fasteners on both ends of the cat with PB Blaster several times over the course of several weeks and still needed an impact wrench to get the nuts off the rear of the cat. We had to cut the bolts off the front of a buddy's cat to get it out. In both cases we were replacing the cat and exhaust and it all comes off as one piece. We never did get the OEM cat off his OEM exhaust even when it was out of the car.

I used new OEM spring bolts. Autozone had some halfway decent spring bolts that he fitted.

You'll need microscopic hands to disconnect the rear O2 sensor and plug back in up there in the driveline tunnel. The front one is on the header pipe.

We did both cars on a lift. Recommend one.

There's, of course, a Mighty Car Mods video where they install the (horrible) Q300 exhaust in 20 minutes. I think they cheated removed the bolts once before! They just lifted the back of the car and slithered under.

-- Chuck

Car Analogy

Do you have an o2 sensor socket? Makes removing them much easier.

Agree that this is one of those projects that ought to go easy, and sometimes does, but often you run into one thing after another and what should take an hour still not done at end of day.

Chris_Lum

just disconnect the O2 sensor at the plug and unscrew the sensor when the cat is off the car, that way you don't need to worry about winding/unwinding the wires.

jack up on all 4 is best and use PB plaster for nuts.

Bruunz

Wow.... thanks for the all the tips. I literally thought this would be a Sunday morning thing.
I'll try and use some WD-40 on Saturday to help.

I don't have a 02 sensor socket or an impact wrench...

I'll update everyone on Monday and we can have a laugh at how little i progressed

Chuck S

PB B'laster, not WD40 (which seems like kerosene). Any auto parts store.



-- Chuck

Chris_Lum

Buy a 22mm crescent wrench or o2 sensor socket and you'll have an easier time any time you have to touch an o2 sensor on a Honda.

Also a small tube of anti seize will go a long way so you can prevent nightmare o2 sensor/cat bolt scenarios.