AEM O2 Wideband Help

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Kilgon

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Just finished up installing my O2 wideband and am getting an error of some type.  I have checked around on the internet and haven't been able to find any videos or sites showing what this problem is.  Before I start trying to get a replacement sensor I figure I would check here to see if anyone else has had this issue and if so what was the fix.   The model is an AEM 30-4110.  After I installed it and before I started the engine with just the key turned on it would go to 14.8 and sit there. When I first started the car for the first time with it in it was indicating a little rich and was reading around 12.9 to 13.5.  I made 2 small adjustments to the carb giving a few minutes in between each one.  It was reading right around 14.9 to 15.4 after these.  I went to adjust it back a smidge and when I cheeked it again it was on the 3 bars.   I thought maybe I set the carb to rich and it limited out.   I let the car sit for around 15 minutes figuring that if it was pegged out that it would get some fresh air and would be ok. There is no fresh air cal on it.  After starting it back up it read for about 5 second and then climbed again to the 3 bars.    I know I am running lean at the moment.  I have a 460 with hookers long tube headers.  Sensor is back about 34" from the last exhaust port on the passenger side - within aem specs.  Also about 15 degrees above horizonal. I checked the wiring and all looks  good.   Any ideas on what  it might be.  See video of what it does when key is turn on.  



 
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Don C

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I would double check the 12 volt supply and the grounding. What do you have them  connected to?

 

Kilgon

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I would double check the 12 volt supply and the grounding. What do you have them  connected to?
Have the 12v from the key side of the fuse for the heater a/c.  Also have 10 amp in line fuse after tie in at the fuse block as directed.  The ground is at the shifter tied in with 2 others.  Voltage checked out ok when installing but will check again tomorrow if it not to cold.    

 

Don C

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If you can't find something obvious I would connect both the positive and negative directly to the battery, see if that makes it work right. Bit of a PITA, but that's one way to make sure.

 

Kilgon

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If you can't find something obvious I would connect both the positive and negative directly to the battery, see if that makes it work right. Bit of a PITA, but that's one way to make sure.
Good idea.  Would eliminate the power end of it. I got the wire!   :biggrin:   Nice thing is It's easy to get to so it won't be hard to do.  Gauge just slides out of the bezel.  

 

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I have the exact same gauge. It takes at least a couple minutes of run time for the gauge to get some heat in it and start to read accurately. It will start lean and continue to indicate richer as the engine heats up and the fuel gets properly vaporized and combusted. To get truly accurate readings the engine should be fully heat soaked.

Is the sensor in the header collector or in the exhaust pipe near the crossover? If near the crossover it could be seeing reversion air from exhaust pulses giving you a false lean reading.

 
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I'm also looking at buying a AFR gauge, but reluctant to spend 200+ US on one just for setting up my motor. I can borrow one as I did before, but does anyone have good info on a cheaper model. I hate to keep borrowing stuff, especially expensive stuff! I see gauges for as little as 40 bucks (Chinese), but no O2 sensor and that seems to be the expensive part.

Any suggestion?

 

Kilgon

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I have the exact same gauge. It takes at least a couple minutes of run time for the gauge to get some heat in it and start to read accurately. It will start lean and continue to indicate richer as the engine heats up and the fuel gets properly vaporized and combusted. To get truly accurate readings the engine should be fully heat soaked.

Is the sensor in the header collector or in the exhaust pipe near the crossover? If near the crossover it could be seeing reversion air from exhaust pulses giving you a false lean reading.
Unit was working for maybe 2 to 3 minutes before it went to max lean (dashes).  I tried making sure the carb was running rich and still the same thing.  The bung is behind the collector about 3" or so and about 4 or 5" in front of the H pipe.  It's about the the only place I can put it.   I also did a direct battery connect as Don C mentioned to eliminate any wiring issues.  Not much more to try so I sent an email off to AEM and will see what they come back with.  I got a feeling the sensor failed.

 

Kilgon

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I'm also looking at buying a AFR gauge, but reluctant to spend 200+ US on one just for setting up my motor. I can borrow one as I did before, but does anyone have good info on a cheaper model. I hate to keep borrowing stuff, especially expensive stuff! I see gauges for as little as 40 bucks (Chinese), but no O2 sensor and that seems to be the expensive part.

Any suggestion?
I got mine AEM30-4110 for $160 off Amazon.  Had some bad reviews about their the sensor being bad out of the box (i think  I got one of the bad ones).  They are a authorize dealer for AEM so I should be able to get a free warranty replacement if that is my problem.    I figure for the money it would be worth a try.  Here is the link and they are now selling them for $135.  

https://www.amazon.com/AEM-30-4110-UEGO-Ratio-Gauge/dp/B00N3VGPYS/ref=sr_1_1?dchild=1&keywords=aem30-4110&qid=1612558059&sr=8-1

 
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I got mine AEM30-4110 for $160 off Amazon.  Had some bad reviews about their the sensor being bad out of the box (i think  I got one of the bad ones).  They are a authorize dealer for AEM so I should be able to get a free warranty replacement if that is my problem.    I figure for the money it would be worth a try.  Here is the link and they are now selling them for $135.  

https://www.amazon.com/AEM-30-4110-UEGO-Ratio-Gauge/dp/B00N3VGPYS/ref=sr_1_1?dchild=1&keywords=aem30-4110&qid=1612558059&sr=8-1
Thanks for getting back on the AFR. I'll check Amazon.ca and see what the price is there. Good to know the sensors may not be the best.

I'll let you know what I decide to do. There's no rush, too damn cold again at 17f today. I can wait till spring!!!

 

Kilgon

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Update on issue. Got a reply back from AEM support.  Was told to remove the sensor from the exhaust and then with it still connect but out of the exhaust to take a rag and saturated it with gas, starting fluid or carb cleaner and then wrap it around the sensor.  Once done turn the key to just the on position and the gauge should go to full rich and stay there until rag is removed and then it should go to full lean, the 3 dashes.   When I tested mine it went to full rich for about 2 seconds and then straight lean.  From this test it would indicate I have a bad sensor.  I sent a email back to them with the test result and am waiting to hear back about getting a warranty replacement.

 
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