• Protip: Profile posts are public! Use Conversations to message other members privately. Everyone can see the content of a profile post.

AEM wideband issues...

Sig

Experienced Member
Rating - 0%
0   0   0
Joined
Sep 25, 2000
Messages
1,604
Location
Tyson's Corner, VA
I had a dual channel wideband installed and it worked perfectly for 2 days then suddenly stopped. Each O2 sensor now reads a staic a/f that is a nonsense number. Each one still indicates that there is voltage going them at a static level of 4.x. All connectors appear in fine shape and there are no obvious problems with the wiring/connectors/controller.

I have heard through the grapevine that the AEM wb's have a reputation for flaking out, but the rumormill can often times be misleading.

Any ideas what the problem or solution may be?
 

Sig

Experienced Member
Rating - 0%
0   0   0
Joined
Sep 25, 2000
Messages
1,604
Location
Tyson's Corner, VA
MiamieNeSeX said:
Have you tried posting on AEMs forum?


Armando

No, but that's a good idea. I figured between Devin, Mark Basch and others that read this forum that someone may have run into this before with the NSX. I will cross-post to the AEM forum.
 
Rating - 0%
0   0   0
Joined
Sep 13, 2001
Messages
323
Location
Lake Mathews (Corona), Ca
I had a similar problem. I messed with the O2 gain settings until it started indicating a reasonable number. When I was done screwing around I had gone full circle back to my original gain settings (1 and .98 I believe on my dual channel) and the bad channel was working fine. Don't ask me why, however. Mark
 

Sig

Experienced Member
Rating - 0%
0   0   0
Joined
Sep 25, 2000
Messages
1,604
Location
Tyson's Corner, VA
mikeh said:
If you disconnect the connector near the O2 sensor, does voltage drop or stay the same? I assume you're reading the voltage as displayed in an AEM EMS and not using a volt/multi-meter?

-mike

I originally viewed it with the voltage with the ems display via laptop. But did a volt meter verification.
 

Sig

Experienced Member
Rating - 0%
0   0   0
Joined
Sep 25, 2000
Messages
1,604
Location
Tyson's Corner, VA
Mark911 said:
I had a similar problem. I messed with the O2 gain settings until it started indicating a reasonable number. When I was done screwing around I had gone full circle back to my original gain settings (1 and .98 I believe on my dual channel) and the bad channel was working fine. Don't ask me why, however. Mark

I will try to see if the gain settings can help. If I remember correctly, the UEGO flaked later in the day after tweaking the gains to calibrate the sensors. Are there gain values that are too high or low that will confuse the controller over time?
 
Rating - 0%
0   0   0
Joined
Apr 5, 2005
Messages
220
Jason,

Sorry I didn't get to this sooner. How did you run the ground wire for the UEGO controller? Grounding to the chassis on an NSX UEGO installation can be the culprit - I've seen it cause problems right away as well as down the road BTW. I believe the installation manual states battery ground as well.

I've made it a practice to run some very good quality wire all the way back from the battery (pos and neg) to the contoller. The battery positive can be sent to a good automotive relay and turned on with switched 12V power behind the passenger seat. Solder the controller ground to the battery ground wire that you've run back.

Please let me know if this works. Maybe you've installed yours this way. Either way, it sounds like the heaters have turned off which will default the voltage to approx 4.0V (you should see an air/fuel number displayed around stoich)
 

Sig

Experienced Member
Rating - 0%
0   0   0
Joined
Sep 25, 2000
Messages
1,604
Location
Tyson's Corner, VA
Jason,

Sorry I didn't get to this sooner. How did you run the ground wire for the UEGO controller? Grounding to the chassis on an NSX UEGO installation can be the culprit - I've seen it cause problems right away as well as down the road BTW. I believe the installation manual states battery ground as well.

I've made it a practice to run some very good quality wire all the way back from the battery (pos and neg) to the contoller. The battery positive can be sent to a good automotive relay and turned on with switched 12V power behind the passenger seat. Solder the controller ground to the battery ground wire that you've run back.

Please let me know if this works. Maybe you've installed yours this way. Either way, it sounds like the heaters have turned off which will default the voltage to approx 4.0V (you should see an air/fuel number displayed around stoich)

Thanks for input Devin. If I remember correctly, both O2's are reading 18.xx. Hopefully, there will be time over the weekend to get into the installation and make sure the grounding was done properly. I'll let you know how it turns out.
 
Rating - 0%
0   0   0
Joined
Sep 13, 2001
Messages
323
Location
Lake Mathews (Corona), Ca
Sig said:
Thanks for input Devin. If I remember correctly, both O2's are reading 18.xx. Hopefully, there will be time over the weekend to get into the installation and make sure the grounding was done properly. I'll let you know how it turns out.

My was also pegged rock solid at 18.xx before I did the old gain trick.
 

Sig

Experienced Member
Rating - 0%
0   0   0
Joined
Sep 25, 2000
Messages
1,604
Location
Tyson's Corner, VA
Mark911 said:
My was also pegged rock solid at 18.xx before I did the old gain trick.

IIIInnnteresting... maybe it will be a simple fix. Hopefully, between screwing around with the gain and checking the ground wiring I will get the thing running properly again.
 

sjs

Legendary Member
Rating - 0%
0   0   0
Joined
Mar 17, 2001
Messages
2,896
Location
St. Louis, Mo.
Devin, why all the way to the battery rather than from the fuse box, at least for positive?

Sig, if the heaters are not on you will quickly "foul" the sensor and they don't generally burn clean again, so you should pull them out or not drive it at all until fixed.
 
Rating - 0%
0   0   0
Joined
Apr 5, 2005
Messages
220
sjs said:
Devin, why all the way to the battery rather than from the fuse box, at least for positive?

Figured I was going through the trouble to run a negative all the way back...might as well keep everything together - at least for diagnostic reasons later. The fuse box will work just fine like you said.

The gain is extremely important as everyone mentioned. You said the gain read 4.x volts - I should have asked how close to 4.0V you meant. 4.0 and 4.9 are a long ways from eachother. At 4.0 (my assumtion previously), the air/fuel parameters should read approximately stoich. As mentioned before, you want to adjust both gains with the sensors unplugged until your O2 #1 and #2 volts read as close to 4.00V as possible.
 
Top