Civic EX 99 cat problems
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Civic EX 99 cat problems
so I’m posting this to hopefully figure out if maybe there is small cheaper fix to the problem then buying a new cat. So I changed the oil pan gasket n had some help from a bud but we took the cat off to get to all the bolts we needed to. After putting everything back together I got the P0420 the o2 sensors are good just changed but I’m hoping that maybe it could of been possible that maybe I didn’t tighten the bolts on the cat tight enough or something. If anyone has any info that’d be helpful thanks
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From: G E Orgi A
Re: Civic EX 99 cat problems
P0420 can be caused by leaks in the exhaust. The leaks allow extra oxygen to get in and make the rear o2 think the cat isn't working.
I just went through this finding a small rust hole around the cat. I was using torque app to monitor o2 voltages and from that discerned that o2s seemed to be functioning, but something else had to be cause.
I just went through this finding a small rust hole around the cat. I was using torque app to monitor o2 voltages and from that discerned that o2s seemed to be functioning, but something else had to be cause.
Thread Starter
Trial User
Joined: Aug 2018
Posts: 2
Likes: 0
Re: Civic EX 99 cat problems
P0420 can be caused by leaks in the exhaust. The leaks allow extra oxygen to get in and make the rear o2 think the cat isn't working.
I just went through this finding a small rust hole around the cat. I was using torque app to monitor o2 voltages and from that discerned that o2s seemed to be functioning, but something else had to be cause.
I just went through this finding a small rust hole around the cat. I was using torque app to monitor o2 voltages and from that discerned that o2s seemed to be functioning, but something else had to be cause.
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