NotACarGuy

Hello, I am new here and could use some help. If I have done anything wrong please move or delete.

I have a 2000 civic lx. Recently the exhaust manifold developed a nice crack that wasn't noticed untill it started throwing code for the o2 sensor. I have gone to the junk yard and as you can imagine, the manifold is one of the first things to be picked. It seems my best bet is to just outright buy a new one. Now I am not really a car guy. I can do minor things but when it comes to part hunting, it's like looking at a book in a foreign language. Can anyone recommend a place to buy a new one that will work and last. I am not looking to do any real aftermarket manifold that involve having to move the o2 sensor and cat. Any info is very appreciated, I have emission tests coming up and I doubt my civic will pass.

Another question that I believe ties into the manifold problem is my idle fluctuates like crazy. Alot of the time when I come to a stop my rpm are so low I am on the verge of dying. A few times it has. Is that tied to the manifold problem or something else?

Thank You all.

Wankenstein

Search this used-part site: http://car-part.com/
Years 1996-2000 (6th gen) and Models DX, LX (base engine) will work for your car's engine

Most likely an issue with the IAC valve: Intake Air Control. Remove it and clean the gasket screen + inside of the IAC with brake cleaner spray. Also, clean the thottle body and blade with thottle body cleaner spray and a toothbrush or rag.

ezone

What was the fault code?
Are there any other fault codes?
Seems to me most sensor failure codes aren't caused by a cracked manifold, more likely simply a bad sensor.

Idle fluctuation is probably not related to the manifold, but none of us can see what's actually happening on your car. Check IAC for sticking? EGR sticking open?
Got video?

I assume your manifold incorporates the catalytic converter? If you have to pass a California emissions test and need a manifold, your choices are limited to OE or C.A.R.B. approved units.
If you're anyplace other than California you can likely get away with far cheaper units, but remember they are cheap for a reason.

If you want to attempt to seal up a crack on the cheap, there have been posts about brazing manifold cracks closed, or maybe using epoxy.

NotACarGuy

Thank you guys. I will check the things you have suggested.

as for the code, when ingot it ran it through out 3

P0132 - oxygen sensor circuit high voltage bank 1 sensor 1 - confirmed -

P0135 oxygen sensor heater bank 1 sensor 1
- confirmed -

P0155 oxygen sensor heater circuit bank 2 sensor 1
- current 152-6 -

I am in Oregon.

ezone

This one is usually just confirm elevated voltage output and if it is high replace the sensor
Ohm test the heater portion of the sensor, probably open circuit if it is bad
Try P0141........If you really got a P0155 then your code reader is lying and cannot be trusted. Check with a couple other different testers.


Got P1298, P0501 codes as well? Alternator not charging?

NotACarGuy

it has been a little bit since I have had them read, and I don't have a reader myself. Those were the only codes being thrown. I will attempt to get them read again to see if anything has changed.

Colin42

go get a $20 bluetooth one off amazon

ezone

My point was that if the code reader you used displayed an impossible code (P0155 is not programmed in that ECM), then it really isn't trustworthy on any other codes either.

Also handy: Writing down the freeze frame data that was stored with the code(s),
and erasing the codes then seeing how long it takes to reset codes (like during one test drive), and which codes did reset.

NotACarGuy

sorry guys, bare with me. When it comes to the all this stuff it goes over my head. Trying my best to work through it all while still driving the car, as it's my daily and work full time.

ezone

Your pic confirms what I said.
That car cannot set code P0155.
Code reader is faulty.

Try a few other code readers (different brands)