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Discussion Starter #1
ive been reading on here about how people who have done a header install say that the CEL comes on after installing the new header. I was wondering if this is true, or if you can slap those things on without triggering the light. since f2 has lowered their prices, i see headers in the near future. i have a 2.0 duratec btw. input?
 

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yes it is true. you will get a cel. one way to get rid of it is to get a tune to disable the rear o2 sensor.
 

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because the rear o2 sensor monitors the cat... and if its not there... the PCM thinks it has failed, thus throws the light for you to bring it to a stealership and then they take your first born and pride..
 

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Head Hurt
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yea but if there are three spots for the O2 sensor then why would the CEL come on?
OK, anyone correct me here if I'm wrong, but my understanding is;

The CAT Ho2S is monitoring for a change in oxygen content compared to the pre-cat Ho2S. With a header the CAT Ho2S is now in the same air stream as the pre-cat Ho2S with no change in oxygen content, bingo CEL.

I had a CEL on my 08' after installing the F2 header, did that mod and haven't seen a CEL since.
 
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Head Hurt
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Lol so could you only do that mod to the 3rd sensor instead of all of them?
The "how to" answers that for you, if you like to experiment (like I do) I'd maybe try just doing one, but be prepared to do both as the "how to" instructs.

PS: The 08' only has 2 sensors. You only have to do one, the one that was in the middle of the CAT (lower one on the header).
 

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Head Hurt
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Alrighty^^^that answers my question. Thanks Brad!
You're welcome, and here's another hint - don't try drilling out the spark plug anti-fouler with one shot using a 1/2" drill bit. Those things are made out of some type of material that eats drill bits. Use gradually larger bits until you get up to 1/2" and you'll save bits and frustration. Even with my drill press the damn thing ate one used and one brand new 1/2" bit before I got smart about it. [hihi]
 

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I'm about to do a header.. is it safe to run with the cel? because i wont have the money for a tune for a while.. will it mess anything up??

thanks

mason
 

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Head Hurt
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You don't need a tune to get rid of the CEL. Check the link in post #4 of this thread and do that mod. It's dirt cheap, it works and you won't have a CEL.

You won't hurt anything running with the CEL caused by the CAT Ho2S. BUT, you also won't know if anything more serious happens that would throw a CEL because it's already on.
 

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Gal. 2:20
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ya agreed youm need to get rid of you CEL some how so you can see it if and when it pops up again.
 

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I did the anti fouler mod and still get a CEL any idea what I might be doing wrong I have 3 sensors the first one I didn't do anything the middle one (the one that went in the cat) I put on drilled anti fouler and the 3rd lowest one I put a drilled and undrilled antifouler my drill bit I used doesn't have the size on it anymore but putting a 1/2" wrench over it show that it was really close

Any ideas??
 

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Gal. 2:20
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you mite have the wrong sensor in...how many bungs do you have and what sensor/s did you put back in and where? You should have three sensors: White,Gray, and Black rite....?
 
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