96 explorer c.e.l.

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Nov 9, 2004 | 09:25 PM

tonyp28840

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96 explorer c.e.l.

I'm hoping someone can help me. My check engine light came on I have a code reader and the code came back 0420-catalyst system efficiency below threshold. Can someone tell me what needs to be repaired? Is it the catalytic converter?

Nov 11, 2004 | 10:40 AM

sllt96xlt

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From: Deer Park

that would be my guess. it is probably getting readings from one of the oxygen sensors, it could be one of those too.

Nov 11, 2004 | 03:15 PM

tonyp28840

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Thanx I might just change both the o2 sensors and the cat. I can't get a definitive answer from anywhere about how to pinpoint which one is the problem. I asked ford and they said that it could be either one of those but they wouldn't tell me how to narrow it down . if anyone knows I would appreciate the help.

Nov 13, 2004 | 07:01 AM

JPrato

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catalyst system efficiency below threshold

How many miles on your 96 explorer? I have the same problem at 126k. I was getting a slow oxygen sensor fault first. That was a few months ago and of course I didn't write down the exact code. (was it the one before or after the cat(s)?) The check engine light would cycle on and off. Then it stayed on with the P0420 code. You can reset it and it will stay for awhile (good for getting it through the emisions test). I'm leaning towards the O2 sensors in that I wouldn't think the cat would be shot at this millage, and I was getting the O2 fault code first. The cat is probably big bucks to replace. I haven't crawl under there in a while, but If my memory is right think I have two cats.

Nov 13, 2004 | 10:10 AM

sllt96xlt

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From: Deer Park

depends on the motor. my 96 v8a has 4 cats.

Nov 13, 2004 | 12:36 PM

tonyp28840

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I have 109Kmiles on my explorer. The Cat was replaced by Ford at 54k miles. my CEL came on then and my mechanic told me it was my cat and that ford warranties them up to 75k. Ford wanted to wait until the cel came on again because when my mech. read the code he cleared it. So I had to wait until the cel cycled again. I've since tried to do most of the work on my car myself. Unless it's a really big job.