Check Engine light – Cat efficiently below threshold
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Check Engine light – Cat efficiently below threshold
I recently bought the car and it had 200,000 miles. It has brand new exhaust muffler system on it including cat (assuming that is the cat in the middle of the pipe under the front seats). The check engine light came on and I went to Advance auto store and borrow the decoder to read in the error and reset the codes yesterday. It came back on today. Is there a problem or is it because the new cat has not been broken in yet. Could there be a problem with one or both of the oxygen sensors?
Any input is appreciated.
Joined: Nov 2007
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RE: Check Engine light – Cat efficiently below threshold
check any sensors that could throw the code. 02 Sensor maybe malfunctioning if the cat is brand new. I worked with Georgia Clean AirForce(EMISSIONS) for 4 yearsand never heard of breaking in a cat, but I could be wrong...
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From: Southern, Ca
RE: Check Engine light – Cat efficiently below threshold
A cat doesn't need to brake IN...I had the same code for my 00 Si. It was my cat that went out on me. If I wouldn't replace my cat soonI would of ended with a bad 02 sensor too.
When your car is on ( engine running) does the exhaust smell like rotten egg, stinky. Those are signs of a bad cat.
Is your car modified???? exhaust don't make a difference. Maybe like a chipped ECU
When your car is on ( engine running) does the exhaust smell like rotten egg, stinky. Those are signs of a bad cat.
Is your car modified???? exhaust don't make a difference. Maybe like a chipped ECU
RE: Check Engine light – Cat efficiently below threshold
So it has new exhaust from the cat back? Have you checked the header? If it's still stock with 200K miles on it, the header might be cracked from wear.
On my old 2000 DX, I was getting that code around 234K, but it turned out that my header had a crack right down the middle, and for some reason the computer was reading the problem as the cat? I can only guess that it had something to do with the fact that exhaust was escaping into the engine bay, resulting in strange readings from the O2 sensors. I went to a salvage yard, grabbed a used header, put it on, and reset the computer. The light didn't come back on.
That's just my 2 cents. Might not be the same as your problem.
On my old 2000 DX, I was getting that code around 234K, but it turned out that my header had a crack right down the middle, and for some reason the computer was reading the problem as the cat? I can only guess that it had something to do with the fact that exhaust was escaping into the engine bay, resulting in strange readings from the O2 sensors. I went to a salvage yard, grabbed a used header, put it on, and reset the computer. The light didn't come back on.
That's just my 2 cents. Might not be the same as your problem.
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RE: Check Engine light – Cat efficiently below threshold
ORIGINAL: Civic Si 00
When your car is on ( engine running) does the exhaust smell like rotten egg, stinky. Those are signs of a bad cat.
Is your car modified???? exhaust don't make a difference. Maybe like a chipped ECU
When your car is on ( engine running) does the exhaust smell like rotten egg, stinky. Those are signs of a bad cat.
Is your car modified???? exhaust don't make a difference. Maybe like a chipped ECU
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RE: Check Engine light – Cat efficiently below threshold
Is the cat right in front of the engine, if so then I have an old Cat. I have two section under the car that is new. I know the one towards to the back of the car is muffler. The other one in the middle of the car is either a cat or some kind of smaller muffler. I never had a Honda before, just big azz chevy and ford truck. I downsize to save on gas.