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Need Help With A Diagnosing A Miss Please

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Old Feb 8, 2006 | 08:03 PM
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Default Need Help With A Diagnosing A Miss Please

I have been chasing down a miss, and can't get it firgured out. It's starting to **** me off too!

Here's the deal.

Put long tubes on the car. Melted input lead to timing tuner a few weeks ago. Repaired that, again a few weeks ago. Ran great for two weeks. Infact, it ran great no problems one night, and the next morning it had a small miss at idle. Drove it, went away at part throttle. Then started coming in at part throttle. The all over the place (over the course of the day). I thought it might be the timing tuner, but when I bypased it actually got worse!

Now, when I did the long tubes, I extened the sensor side of the O2's. A few people told me this was wrong, so I figured this was the problem and rectified that by doing the pcm side. Even used a different set of o2's (the old rears) and had the same problems. Low voltage bank one and two on the O2's and a multiple missfire code. At first, at and after 3000 rpm, basically full throttle, it was fine but now it's back firing and **** too. When I limped the car home, I actually saw my SES light flashing at me, a first for me!

Is low voltage lean, or fat? The car is dumping fuel through the motor like it's going out of style. I don't know if the code is because of the extra fuel after the fact, or because of a lean condition caused by somethig elsemaking it dump the extra fuel.

I have a set of new plugs, but haven't put them in yet. I was thinking maybe tps, mass air meter, possibly a bad coil at this point? Anyone know how to test a coil to see if it's working? Or the other sensors?

Any ideas, sugestions. I am not new, I just don't post here much, so no flaming or newbee hazing bullshit.

I don't know much about electronics or f/i. I just know the components and where you would normally start looking to fix something like this, but coming up empty handed. I am just trying to avoid throwing a bunch of parts (money which I don't have!) at it trying to figure it out!

Thanks Guys,
ANTIVNM

www.fuelslut.net
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Old Feb 8, 2006 | 08:48 PM
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low is a lean condition

If you have access to a scanner or scope take a look at the millivolts and how the O2s are switching. I just went through this same thing, low O2 volatage on bank 2 (B2) was causing misfires all down bank 2 as well as a major fuel trim problem where the long term fuel trim was +25% and the injector pulse width on B2 was twice that of B1 (6 millivolts vs 3 millivolts).

I solved the problem by installing new O2 (primmary).
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Old Feb 9, 2006 | 05:35 PM
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Is there a difference between the front and rear O2's? Can you interchange them?
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Old Feb 11, 2006 | 09:40 AM
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Originally Posted by I8YOR50
Is there a difference between the front and rear O2's? Can you interchange them?
Well, I called the dealership and asked the parts department. Front and rear there is no diference, but there is a left and right side part number!

I have an account there, and even with my account they are like $200 for a pair!

I know I didn't keep them oriented side to side (not sure if they are in backwards or not) in any way when I extended the pcm side of the O2 harness and put the rear set in place (the rears are deleted with HP Tuners and I had the old rears) of the fronts.

So I am off to swapp them side to side, and go have Autozone clear the codes in the pcm since the guy I know here in Orlando with HP Tuners hasn't been answering my messages for 2 weeks now!
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Old Feb 11, 2006 | 11:09 AM
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All 4 O2's are the same. The part # difference is for the length of the cable on the end of the sensor.
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Old Feb 11, 2006 | 05:54 PM
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well, i think i might have gotten it licked. i swapped the O2's around, and it made almost no difference. SO i said **** it and put in a new set of tr6's. the old ones looked ok when they came out! Anyone know how to set up a multi meter to check a sprak plug? Anyway, that seems to have worked, so I guess it was a plug all along. Oh well, at least I fixed my O2 harness and got it right again. I am happy!
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Old Feb 12, 2006 | 02:40 PM
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WELL SO MUCH FOR BEING HAPPY!

Drove fine for a few hours. Went to the local hang out and let it sit for half an hours. got in it, and started it, and the problem is right back. mothaf'er, i am so pissed right now~!
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Old Feb 13, 2006 | 05:12 AM
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Default Another idle/o2 problem

opps....thought i hit "new thread",sorry
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Old Feb 13, 2006 | 07:58 AM
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check your plug wires
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