O2 Sensor/Wideband Issues

[Fleecer]

Does anyone have a part number to a quality O2 sensor with a short cord that fits perfectly? I hate having to tie up a bunch of slack in the cord

Years ago someone provided a part # here, but I'm unable to find the post.

I've changed the title and edited my post, as I didn't want to create another. It appears my issue is not the O2 sensor, as I've replaced it and still won't read AFRs. I'm wondering if the wideband crapped out??

I have an AEM X Series wideband. When I turn key on, both red and green lights flash once as it powers up, then green light flashes constantly. Sensor will not warm up in my hand. I removed the small cover on the back, put it in Free Calibration Mode, no change. Recalibrated it to Calibration Mode ( Default), still no change.

The green light flashes quickly for about 30 flashes, gives 1 red flash, then 30 more green flashes.

No matter what I do, I can't get the 02 sensor to heat up. Can anyone shed any light on this issue?

 

[fatchance]

I just trim off the extra Glen and solder it to the correct length.

 

[Fleecer]

I just trim off the extra Glen and solder it to the correct length.

Great idea Steve, but it appears my O2 sensor might be good. I've edited the post.

 

[Richard Hodgins]

Are you using it for closed loop or just running it for an AFR gauge?

 

[Fleecer]

Are you using it for closed loop or just running it for an AFR gauge?

Both

 

[0degC]

Does anyone have a part number to a quality O2 sensor with a short cord that fits perfectly? I hate having to tie up a bunch of slack in the cord

Years ago someone provided a part # here, but I'm unable to find the post.

I've changed the title and edited my post, as I didn't want to create another. It appears my issue is not the O2 sensor, as I've replaced it and still won't read AFRs. I'm wondering if the wideband crapped out??

I have an AEM X Series wideband. When I turn key on, both red and green lights flash once as it powers up, then green light flashes constantly. Sensor will not warm up in my hand. I removed the small cover on the back, put it in Free Calibration Mode, no change. Recalibrated it to Calibration Mode ( Default), still no change.

The green light flashes quickly for about 30 flashes, gives 1 red flash, then 30 more green flashes.

No matter what I do, I can't get the 02 sensor to heat up. Can anyone shed any light on this issue?

As you likely know the green light I believe should be on solid after warmup. Check directions for your controller how the lights are flashing means something fault wise. If you have ruled out o2 sensor as problem and have good power to your controller your controller is likely faulty. It’s also possible you got a bad new sensor.

 

[Fleecer]

Thanks for chiming in. I tried 2 different sensors with the same results. I spoke with a tech at AEM and he told me the controller was bad. I bought another controller, albeit, the plugs were different, rewired it with my old harness and still same issue.

So....figured issue was with harness. Checked continuity in all the wires, and all tested good. Figured must be a wire half chaffed with intermittent issues. Cut harness up and did not find any issues.

Then I thought perhaps my original controller is bad, and perhaps the new one I bought is not compatible? So ......I thought, "Well TD is having a 15% sale, I may as well get a new controller". So placed the order and then found out there is no discount on AEM electronics.

Arghhhh......why couldn't I have embraced a cheaper hobby like stamp collecting or basket weaving???

 

[0degC]

Thanks for chiming in. I tried 2 different sensors with the same results. I spoke with a tech at AEM and he told me the controller was bad. I bought another controller, albeit, the plugs were different, rewired it with my old harness and still same issue.

So....figured issue was with harness. Checked continuity in all the wires, and all tested good. Figured must be a wire half chaffed with intermittent issues. Cut harness up and did not find any issues.

Then I thought perhaps my original controller is bad, and perhaps the new on I bought is not compatible? So ......I thought, "Well TD is having a 15% sale, I may as well get a new controller". So placed the order and then found out there is no discount on AEM electronics.

Arghhhh......why couldn't I have embraced a cheaper hobby like stamp collecting or basket weaving???

This is an odd one for sure! I would have done same as you and purchased the controller elsewhere and wired in the Gap harness, should work fine. Do you measure about 3 ohms on your heater pins on your sensors? Check your chassis and engine grounds on your sled? Try powering your controller from a separate source other than sled voltage, maybe bad voltage regulator and you have dirty DC? Just some long shots to try. Frustrating for sure.

 

[earthling]

Everything in these sensor suites (o2, baro, map) is ground referenced, probably including the gauge itself. Check from sensor to ground at the sensor (frame/block/etc) and check from the gauge to ground, and between those ground sources. Any floating of ground between them will cause problems. @0degC has a good suggestion to basically bench test everything by using a separate power and ground (another battery), isolating everything from the sled.

 

[Fleecer]

While trying to figure things out I powered and grounded the AEM Module to a separate battery and still no dice. I went to another sled with wideband/O2 sensor and both my new/old modules would not work. This led me to believe both modules were faulty, but I could be wrong......

I'm glad you chimed in Earthling, as I have an electrical question you may be able to answer. In conducting some additional research on WHY the new module would not work with original harness, I learned that the Can Bus in the new module may not match the old module? Can a guy check the Can Bus or change it to match? What is Can Bus?

 

[KnappAttack]

Glenn,
When I had an original AEM module go bad, I just ordered one off of Amazon, cut the plug off the original one and spliced it onto the Amazon bought AEM module. It worked like a champ since and I have it on my 23 now too, works fine. Someone said something here about a Can Bus and the replacement wouldn't work on a replacement bought anywhere but the GAP one yada-yada, but it worked fine for me so go figure. I try to steer clear of busses anyway... so works for me.

 

[earthling]

While trying to figure things out I powered and grounded the AEM Module to a separate battery and still no dice. I went to another sled with wideband/O2 sensor and both my new/old modules would not work. This led me to believe both modules were faulty, but I could be wrong......

I'm glad you chimed in Earthling, as I have an electrical question you may be able to answer. In conducting some additional research on WHY the new module would not work with original harness, I learned that the Can Bus in the new module may not match the old module? Can a guy check the Can Bus or change it to match? What is Can Bus?

Canbus is a two wire network sending digital signals around instead of analog voltages. Ironically, one way to check a canbus system is the gauge you have. I am not familiar with the O2 sensors and modules. I assume that the o2 sensor is still analog (0-1v or 0-5v). Connects through some kind of adapter to turn it into canbus messages, and then that eventually feeds through the canbus network to the flasher module.

One way to check canbus is to use an OBDII reader. The flasher harnesses I have seen just look like OBDII compliant devices and the harness looks like it connects to the sleds diagnostic port on one side and the flasher port on the other. If so, that is likely just canbus messages feeding into the flasher and ECU. If the flasher module is just the diagnostic wires plus power and ground you could try plugging in an automobile OBDII reader. I don't know why the canbus messages would not be standard but who knows what is happening in that little harness.

When you say module do you mean the wire harness that plugs between the o2 sensor and the canbus network?

The below is what I found for AEM, and it looks like what appears in the images on the TD website. If it is something like this then you can use normal O2 sensor testing to see if the sensor is working and likely ODBII to read the canbus messages at the diag port (or flasher port) to see if the O2 readings are showing up. Worth a shot anyhow.

 

[earthling]

Stepping back for a second. If you have another sled with a working O2 sensor, can you plug it into the non-working sled? Or, you can extend the two sensor wires from the working sled with a temporary set of jumper wires to the gauge on your non-working sled, they will be noisy because you would not have proper twists or shielding but it should be enough to get the gauge to recognize it. You have to find a way to prove to yourself that either the gauge is bad or the sensors are bad.

@KnappAttack which part did you buy off of Amazon? If it is an off the shelf sensor then the canbus messages will be standard, automotive canbus messages.

 

[0degC]

While trying to figure things out I powered and grounded the AEM Module to a separate battery and still no dice. I went to another sled with wideband/O2 sensor and both my new/old modules would not work. This led me to believe both modules were faulty, but I could be wrong......

I'm glad you chimed in Earthling, as I have an electrical question you may be able to answer. In conducting some additional research on WHY the new module would not work with original harness, I learned that the Can Bus in the new module may not match the old module? Can a guy check the Can Bus or change it to match? What is Can Bus?

I think you have proven you have 2 bad controllers unless you have wired the new one wrong, and I am sure you have checked that to be sure a few times by now.

 

[Fleecer]

Canbus is a two wire network sending digital signals around instead of analog voltages. Ironically, one way to check a canbus system is the gauge you have. I am not familiar with the O2 sensors and modules. I assume that the o2 sensor is still analog (0-1v or 0-5v). Connects through some kind of adapter to turn it into canbus messages, and then that eventually feeds through the canbus network to the flasher module.

One way to check canbus is to use an OBDII reader. The flasher harnesses I have seen just look like OBDII compliant devices and the harness looks like it connects to the sleds diagnostic port on one side and the flasher port on the other. If so, that is likely just canbus messages feeding into the flasher and ECU. If the flasher module is just the diagnostic wires plus power and ground you could try plugging in an automobile OBDII reader. I don't know why the canbus messages would not be standard but who knows what is happening in that little harness.

When you say module do you mean the wire harness that plugs between the o2 sensor and the canbus network?

The below is what I found for AEM, and it looks like what appears in the images on the TD website. If it is something like this then you can use normal O2 sensor testing to see if the sensor is working and likely ODBII to read the canbus messages at the diag port (or flasher port) to see if the O2 readings are showing up. Worth a shot anyhow.

View attachment 175867

Earthling, I think I now understand what you mean by canbus, as in the harness, there are 2 wires intertwined/wrapped together strategically. I thought this was done intentionally to create some sort of resistance and tried my best to maintain the same wrap when splicing the old harness to the new module. By module, I'm referring to the black box that says, AEM X Series.

I really appreciate all the help, but at this point I'll pause my diagnosing, as I have a brand new module in mail from TD and will try it once it arrives next week. If that doesn't fix it, I'll report back.

At my age, I'm running out on hair to pull out in frustration. I'll keep you all posted on the results.