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Civic without a CAT

A friend of mine just inherited a 1986 civic . . . 150,000 miles, runs OK, decent shape. The CAT is shot, however . . . or should I say the flange where it connects to the center pipe is rusted away. He wants to replace it with straight pipe. There is no O2 sensor on the CAT. Aside from the legal . . . we live in the sticks where no emission inspection is required . . . what could this do besides pollute a little more? Rocketman

Guess it’d work. If it was me, I’d get an aftermarket cat from NAPA and put it on.

Nothing. If you have no inspection requirement then put in a straight pipe.

There are short adapter pipes which could join that which nature has unjoined. They have them at many auto parts stores for $2 or $3.

Added: These are adapters about 4" long to join pipes of different diameters. Just measure the inner diameters and the outer diameters of the old pipe ends and get adapters to connect.

i agree with this, the car is 22 years old, if they aren’t running 20k miles a year in it, it should be alright.

Thet were called “test pipes” here in AZ.I think they all got pulled off the shelves.

My thoughts exactly . . . I’ll go over it with him to double-check for a sensor, but I didn’t even see a fitting for one. Thanks folks, I’ll let you know how it works out. Rocketman

On an '86 the O2 sensor is on the exhaust manifold next to the engine.

It’s amazing how many posts start with the words “a friend of mine…”

If you type “a friend of mine” in the search window, you get about 6000 posts…

And, you can tell your “friend” that the oxygen sensor isn’t very expensive, either. http://www.autozone.com/N,16100117/shopping/partTypeResultSet.htm

I had a split in my catalytic converter in a former car that the muffler guys welded back together and had no problems at dmv. Go green patch it and be sure there are not going to be any problems due to back flow pressure.

You would get busted for removing the cat here in AZ.Think Federal law also.

Caddyman, A Friend Of Mine Did Exactly That! You Are Correct!

CSA,
How in the world do you get those bold (super cool) letters?!

Thanks circuitsmith . . . I’ll look for it in the engine compartment and not underneath. Rocketman

Remember what Harry Bailey said when he toasted his brother George at the end of “Its’ a Wonderful Life”? Rocketman

Hello Kit, What Bold (Super Cool) Letters ?!