Have a 98 civic ex with a empty converter. Keep getting codes 138 and 136. Replaced secondary 02 sensor twice now check engine light will stay out for a couple months and then comes back on. Using NTK sensor, also tried spark plug non foulers but light will come back on in time.

 

Anyone?

 

138? 136? Do you mean P0136 and P0138? Are you sure about those? One is a low voltage code, and the other is a high voltage code. They're kind of mutually exclusive.

Reset your ECU and see which returns. Are you running any modifications other than the (stupidly) gutted cat?

 

Did you setup the spark plug defoulers like this ?: How To: Install An O2 Sensor Non Fouler to Eliminate a Check Engine Light with Pics - Chevrolet Colorado & GMC Canyon Forum

You're not going to get any HP gains from gutting the cat converter. However, if you have a manual transmission it will help it shift smoother and the exhaust note sounds ballsier.

 

That...what? No, your exhaust doesn't control how hard your car is to shift. Two completely separate systems. Also, raspier + louder != "ballsier". That's just silly, borderlining on dumb. That's not even getting into how painfully misinformed your signature is...

 

Well Lord, Almighty, All Knowing.. I have to disagree with you.
My signature is obviously in jest.. (keyword: obviously)
By the way how's the engine build going?

 

It's going. It's also irrelevant to how wrong you are about exhaust making your car shift smoother.

 

Just bustin' your nards.

It does help it shift smoother I"know" someone (not me..wink wink)..
who did it on two different makes of cars and absolutely shifted smooth due to less back pressure. Theory vs. reality I guess.

 

If (and I mean if) that were true, the cat of this person you know was clogged or damaged, and needed to be replaced anyway.

 

Nope. Both cats were fine before removal.. lots a light shining through, no CEL's.
What I mean by a ballsier sound is that it has a slightly deeper note than stock and sounds a **** ton better than annoying ricey fart cans.

 

Yes PO136 and PO138 converter was only gutted because it was the insides were loose and rattling. I've cleared codes three time now and they both wil come back but usually takes about a month of driving. Also replaced sensor twice. Not getting PO420 that is usually what you get with high flow converter or test pipe.

 

P0136 is not a Honda code. What are the codes when you jump the service connector.

 

Really? Why not? It's just a generic secondary O2 sensor low voltage code...does Honda use a different code or something?

 

It appears that there's only one code - P0138 - and that the other is just a redundant generic version. However, the OP should verify by jumping the service connector.

 

Also normally I don't drive car but this time when I was driving and the check engine light came on. I was driving about 55-60 there was a little surge in power then light came on immediately.

 

Jump the service connector. It's important to know whether you're dealing with one code versus more.

Google the 96-00 Civic service manual. Follow the troubleshooting steps for the codes you recover.