CEL, P0420 on RX8 series 1 2005
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CEL, P0420 on RX8 series 1 2005
Hi all
I have looked through the forums and have been able to get some good info on this CEL code so far, but wads after more clarification please.
My IOBD device shows the code as P0420 Catalyst System Efficiency Below Threshold Bank 1
I was travelling at 90Kmh on a freeway when it threw the code. Pulled over checked the IOBD and reset it.
So far it has not come back on yet. that was today though.
I recently had my coil packs go out on me and it I am concerned the cat got damaged. The packs were replaced along with the plugs.
I am chasing advise on whether this could be cat or oxygen sensor or both? I am aware that coils can cause cat failure if too much fuel gets down into the cat.
If so , is there a good cat that I can use that is not OEM as the Mazda ones are very expensive. How do you distinguish between cat and oxygen sensor problem?
Cheers
Ice
I have looked through the forums and have been able to get some good info on this CEL code so far, but wads after more clarification please.
My IOBD device shows the code as P0420 Catalyst System Efficiency Below Threshold Bank 1
I was travelling at 90Kmh on a freeway when it threw the code. Pulled over checked the IOBD and reset it.
So far it has not come back on yet. that was today though.
I recently had my coil packs go out on me and it I am concerned the cat got damaged. The packs were replaced along with the plugs.
I am chasing advise on whether this could be cat or oxygen sensor or both? I am aware that coils can cause cat failure if too much fuel gets down into the cat.
If so , is there a good cat that I can use that is not OEM as the Mazda ones are very expensive. How do you distinguish between cat and oxygen sensor problem?
Cheers
Ice
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It is easy to test if it's the cat, just drop the front end and look in. P0420 will only be thrown for a cat failure if the catalyst elements are gone.
See this prior post of mine for what you might see inside the cat: https://www.rx8club.com/series-i-tro...2/#post4592977
See this prior post of mine for what you might see inside the cat: https://www.rx8club.com/series-i-tro...2/#post4592977
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Thanks
So you mean if the cat is not clogged or cracked it maybe something else like the oxygen sensor.
I don't have access to a car hoist so getting the exhaust apart is going to be difficult. I would have to take it to Mazda and they charge like a wounded bull.
I drove it again for another hour after resetting the code and it has not done it again, but does that mean nothing in that it may throw it again at anytime?
I guess I will only know once the cat is looked at properly.
So you mean if the cat is not clogged or cracked it maybe something else like the oxygen sensor.
I don't have access to a car hoist so getting the exhaust apart is going to be difficult. I would have to take it to Mazda and they charge like a wounded bull.
I drove it again for another hour after resetting the code and it has not done it again, but does that mean nothing in that it may throw it again at anytime?
I guess I will only know once the cat is looked at properly.
#4
Wicked Performance
It may be just the cat. Aftermarket cats are hit and miss, meaning some will last most wont. Due to the extreme high heat of our engines most cat will burn too hot and come apart fast. It may be the O2 but usually those throw a different code i believe dont quote me tho been a long day lol
#5
You gonna eat that?
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It is easy to test if it's the cat, just drop the front end and look in. P0420 will only be thrown for a cat failure if the catalyst elements are gone.
See this prior post of mine for what you might see inside the cat: https://www.rx8club.com/series-i-tro...2/#post4592977
See this prior post of mine for what you might see inside the cat: https://www.rx8club.com/series-i-tro...2/#post4592977
The front half of my cat was mostly gone except for 1 egg shaped piece and the back half was intact but clogged.
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I guess the only way to find out is to have the pipe apart and take a look inside.
I tell you what bugs me though. My coil packs died.......does this mean I automatically have buggered my cat? I just cannot believe they would make an engine that cooks a cat just because coil packs die. We do not get the extended warranty in our country either.
Is there any chance it will just go away...lol How much does a reasonably good cat cost fitted?
I tell you what bugs me though. My coil packs died.......does this mean I automatically have buggered my cat? I just cannot believe they would make an engine that cooks a cat just because coil packs die. We do not get the extended warranty in our country either.
Is there any chance it will just go away...lol How much does a reasonably good cat cost fitted?
#7
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Your wasting valuable time on this if it is the CAT and it's clogged your doing damige to your engine. Get it off the car and check it out to confirm yes or no wether it's clogged worry about what els it could be once you confirm the point at hand.
#8
You gonna eat that?
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I guess the only way to find out is to have the pipe apart and take a look inside.
I tell you what bugs me though. My coil packs died.......does this mean I automatically have buggered my cat? I just cannot believe they would make an engine that cooks a cat just because coil packs die. We do not get the extended warranty in our country either.
Is there any chance it will just go away...lol How much does a reasonably good cat cost fitted?
I tell you what bugs me though. My coil packs died.......does this mean I automatically have buggered my cat? I just cannot believe they would make an engine that cooks a cat just because coil packs die. We do not get the extended warranty in our country either.
Is there any chance it will just go away...lol How much does a reasonably good cat cost fitted?
I was almost sure there was nothing wrong with mine at first because it seemed to run fine and only started to run bad after several weeks of trying all kinds of easy remedies to no avail.
I replaced mine with a BHR midpipe over a year ago and have until August to get it inspected.
The OEM cat here is in the neighborhood of $1400 U.S.
#9
You gonna eat that?
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Fwiw my '04 GT had less than 19k miles on it when the cat went bad from only 1 bad coil & plug.
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How do I tell if it is fried without taking it off? The car drives perfectly , plenty of power and no hesitation whatsoever. I will need to get to a car hoist so will have to drive it.
They need a warning light on the dash........it would read "your CAT is fried, get out and walk"
They need a warning light on the dash........it would read "your CAT is fried, get out and walk"
#13
You gonna eat that?
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Some aftermarket cats don't last.
If you have to put off buying a proper cat, you can gut it in the meantime if you have to drive it.
#14
You gonna eat that?
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How do I tell if it is fried without taking it off? The car drives perfectly , plenty of power and no hesitation whatsoever. I will need to get to a car hoist so will have to drive it.
They need a warning light on the dash........it would read "your CAT is fried, get out and walk"
They need a warning light on the dash........it would read "your CAT is fried, get out and walk"
Another way is to jack it up and hit it to see if the strata is broken up, it will rattle, but won't if it's clogged.
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So if it is gutted doe sit still pose a problem with causing engine damage.
I need to understand what is meant by don't drive it if it is fried? Why? Do you mean if it is clogged or simply not there having been blown out the back....
I will need to get it foxed properly, but don;t want to cook my engine on top of this cat issue.
I need to understand what is meant by don't drive it if it is fried? Why? Do you mean if it is clogged or simply not there having been blown out the back....
I will need to get it foxed properly, but don;t want to cook my engine on top of this cat issue.
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By the way
which part is the CAT, the first bulge after the engine or the second bulge. If it is the first bulge in the pipe what is the second one for?
Thanks
which part is the CAT, the first bulge after the engine or the second bulge. If it is the first bulge in the pipe what is the second one for?
Thanks
#17
You gonna eat that?
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So if it is gutted doe sit still pose a problem with causing engine damage.
I need to understand what is meant by don't drive it if it is fried? Why? Do you mean if it is clogged or simply not there having been blown out the back....
I will need to get it foxed properly, but don;t want to cook my engine on top of this cat issue.
I need to understand what is meant by don't drive it if it is fried? Why? Do you mean if it is clogged or simply not there having been blown out the back....
I will need to get it foxed properly, but don;t want to cook my engine on top of this cat issue.
Gutting it allows the exhaust to flow freely, but will not pass emissions testing.
You also have to be sure there are no chunks blocking the exhaust beyond the cat.
There is a DIY here on gutting cats.
#18
You gonna eat that?
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If you get a midpipe, a resonated one would be quieter.
My BHR midpipe has one.
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