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Unread 02-19-2013, 04:05 PM   #16
Rodney88
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yeah i think that's exactly whats going on, pulled the plugs on the 02 sensors and nothing changed (nor did it throw a code) kinda weird.. guess ill be going to the muffler shop soon. checked all my plug wires, everything looked fine, no lose connections. so when i find out ill keep everyone updated, thanks again guys!

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Unread 02-19-2013, 04:13 PM   #17
ZeeJay1997
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The cat failed for a reason, usually because it was running rich or backfired.

If the cause has not been corrected, the results will be the same.
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Unread 02-19-2013, 04:15 PM   #18
jnowak
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Quote:
Originally Posted by xtremzj View Post
Blinking CEL means a hard misfire. DO NOT DRIVE IT WITH A BLINKING CEL!!!
This. Downstream 02 is reading to much 02.
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Unread 02-19-2013, 05:17 PM   #19
Rodney88
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so what your saying is that if the cat IS clogged (witch i dont know yet) your saying if i replace it, it is just going to get clogged again?
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Unread 02-19-2013, 05:24 PM   #20
ZeeJay1997
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Not necessarily, I went back and read the origin of the problem. If the cat was hot and you submerged it it in water, that could have done it in.
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Unread 02-19-2013, 05:26 PM   #21
jnowak
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Quote:
Originally Posted by Rodney88 View Post
so what your saying is that if the cat IS clogged (witch i dont know yet) your saying if i replace it, it is just going to get clogged again?
No you have a misfire. Think of a cat as a fire place. What does fire need, fuel and air. The more it gets, the bigger it gets. The blinking light is saying the downstream is getting to much 02. When you have a misfire ,the fire and air in the cylinder is not getting burnt so gas and fresh air is getting to the cat. And it a vicious cycle. The upstream 02 reads to much air so than it tells the pcm to dump my gas thus adding more unburnt gas to the cat. So it is getting really hot and can blow up.
From what you said that it only blinks when you get on it, I bet that your spark plugs need changing. Classic sign of failing plugs is loss of power under extreme load. Etc hard acceleration or pulling up a hill.
I have seen this a many of times.
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Unread 02-19-2013, 05:29 PM   #22
xtremzj
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I have no idea why people are saying cat. Its common knowledge that a blinking check engine light is a misfire. The problem is before the cat, what a CEL blinking is saying that you are destroying the cat while you drive it.

Cats don't just up and fail, its a gradual thing unless something catastrophic happens. They will usually glow red or rattle around. Did you check the code?
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Unread 02-19-2013, 05:42 PM   #23
ZeeJay1997
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Misfire monitor looks at crank sensor signal.

The engine misfires at high loads because it cant breathe.
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Unread 02-19-2013, 05:56 PM   #24
jnowak
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Quote:
Originally Posted by xtremzj View Post
I have no idea why people are saying cat. Its common knowledge that a blinking check engine light is a misfire. The problem is before the cat, what a CEL blinking is saying that you are destroying the cat while you drive it.

Cats don't just up and fail, its a gradual thing unless something catastrophic happens. They will usually glow red or rattle around. Did you check the code?
::thumbs up::
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Unread 02-19-2013, 06:11 PM   #25
ZeeJay1997
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Quote:
Originally Posted by Rodney88 View Post
did a little off roading
Quote:
Originally Posted by xtremzj View Post
unless something catastrophic happens.
The question is, did the OP drive his jeep through water? If so, odds are the cat is plugged
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Unread 02-19-2013, 06:34 PM   #26
jnowak
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Options

1.$20 or so in spark plugs

2. $100+ at a muffler shop

Dealers choice.
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Unread 02-19-2013, 06:36 PM   #27
xtremzj
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Yeah but people drive through puddles all the time, you don't see an over abuntence of clogged cats. In fact a clogged cat is rare. Plus it's pretty hard to clog a cat, I punched mine out on my jeep and it takes a lot to "clog" it. It takes time, not just one dip in cold water.

If it was that bad it would have. Hard time running at any rpm not just WOT.
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Unread 02-19-2013, 06:55 PM   #28
ZeeJay1997
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Quote:
Originally Posted by xtremzj View Post
If it was that bad it would have. Hard time running at any rpm not just WOT.
I've never ran a 5.9, but i can say with certainty this is not the case with 4.0
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Unread 02-20-2013, 05:31 AM   #29
ratmonkey
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Quote:
Originally Posted by jnowak View Post
No you have a misfire. Think of a cat as a fire place. What does fire need, fuel and air. The more it gets, the bigger it gets. The blinking light is saying the downstream is getting to much 02. When you have a misfire ,the fire and air in the cylinder is not getting burnt so gas and fresh air is getting to the cat. And it a vicious cycle. The upstream 02 reads to much air so than it tells the pcm to dump my gas thus adding more unburnt gas to the cat. So it is getting really hot and can blow up.
From what you said that it only blinks when you get on it, I bet that your spark plugs need changing. Classic sign of failing plugs is loss of power under extreme load. Etc hard acceleration or pulling up a hill.
I have seen this a many of times.
What in the actual heck are you rambling about?
Quote:
Originally Posted by xtremzj View Post
I have no idea why people are saying cat. Its common knowledge that a blinking check engine light is a misfire. The problem is before the cat, what a CEL blinking is saying that you are destroying the cat while you drive it.

Cats don't just up and fail, its a gradual thing unless something catastrophic happens. They will usually glow red or rattle around. Did you check the code?
You two can finish patting each other on the back and stop leading this guy around to who knows where any time.
Quote:
Originally Posted by ZeeJay1997 View Post
Misfire monitor looks at crank sensor signal.

The engine misfires at high loads because it cant breathe.
This, exactly.
Now, he may have damaged o2 sensor wiring, but probably not.
It's not uncommon to break the catalyst or crimp the exhaust partially closed while playing in some rocks.
Poor acceleration after a certain speed/rpm and major misfire combined with the offroad action just prior to it would lead most of us here to inspect the cat and exhaust for damage.
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Unread 02-20-2013, 05:37 AM   #30
ratmonkey
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Quote:
Originally Posted by xtremzj View Post
Yeah but people drive through puddles all the time, you don't see an over abuntence of clogged cats. In fact a clogged cat is rare. Plus it's pretty hard to clog a cat, I punched mine out on my jeep and it takes a lot to "clog" it. It takes time, not just one dip in cold water.

If it was that bad it would have. Hard time running at any rpm not just WOT.
You've never had a clogged cat...I can tell.

I've seen and experienced probably a dozen between my cars and my friends'.
You obviously have no idea how the vehicle behaves with a bad cat.

They usually run just normal at idle and up to a certain speed/engine load and then you get no more power to accelerate.

For future reference do not talk about hollowed cats on this forum. It is illegal everywhere in the us and not discussed on this forum.
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