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afr gauge help

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Old 05-31-2010, 02:34 AM
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TheLlamaGod
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Default afr gauge help

i just put in my narrowband afr gauge and it has only one light lit up at idle and only a few when i full throttle. my car cant be running that lean all the time.
its an autometer gauge. what could be causing this?
TIA for the help
Old 05-31-2010, 04:41 AM
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nobody can help? the car has 3fpr, mbc, 951 max chip set. idk why it would be running so lean
Old 05-31-2010, 06:24 AM
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Bad O2 sensor perhaps.
Old 05-31-2010, 07:29 AM
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TheLlamaGod
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how do i test an o2 sensor to see if its bad?
also, if my car was running as lean as the gauge says it is. wouldnt i notice a difference in how it drives?
because my car seems to be running as good as ever.

Last edited by TheLlamaGod; 05-31-2010 at 10:26 AM.
Old 05-31-2010, 05:20 PM
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Hook up a voltmeter to the O2 sensor - you should see it dithering around .5v when the car is warmed-up and idling.
Old 05-31-2010, 11:41 PM
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TheLlamaGod
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at idle i was getting 8.5 mV
that seems crazy low compared to .5 v.
what does that mean?
Old 06-01-2010, 12:07 AM
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If you hit the throttle, does the voltage change? If not, then your O2 sensor is bad...
Old 06-01-2010, 12:16 AM
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well today when i was driving, the gauge showed no lights. and when i did WOT it showed one lit. so the voltage is changing.
Old 06-01-2010, 12:51 AM
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this happend to me not to long ago. same gauge and it wouldnt light up or sometimes lights up red. I make the computer (LINK AFM) abit richer but nothing. i changed the O2 sensor and the gauge lit up
Old 06-01-2010, 04:28 AM
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wouldnt my car run weird though if i had a bad o2 sensor?
Old 06-01-2010, 07:52 AM
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alxdgr8
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Originally Posted by TheLlamaGod
i just put in my narrowband afr gauge ...
Well there's your first problem...
Old 06-01-2010, 08:00 AM
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its hard to tell. when you do is turn the car on and un plug it and see if it runs the same
Old 06-01-2010, 10:27 AM
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Don't waste you time with a narrowband for a turbocharged car - completely useless and really dangerous to count on. Throw that thing away and buy an Innovate A/F meter or a Zeitronix. Don't go onto boost until you know what your A/F curve is unless you like swapping out short blocks. It is very easy to destroy these aluminum cylinder walls with mods.
Old 06-01-2010, 08:59 PM
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for the wide band do you have to make a new place to put the sensor?
Old 06-01-2010, 11:32 PM
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You'll need a bung welded on after the turbo for a good reading and sensor longevity. If you buy the Innovate setup is comes with the bung and any muffler shop would weld it on for you with the muffler still on the car.

I am not sure where you are located but if it is near Atlanta I can recommend a shop. Might want to add that to your profile.

If you search on the forums you'll see the pics of the optimal place to put it. Wiring it up is really easy - just need power and ground and hook up the sensor to the gauge and you are good to go. I would pick up one of the metal guage holders for under the radio that Lindsey sells.


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