Constant Adjustment of A/F Levels

[IJ.]

I would

If you can afford to replace them often they can stay where they are.

Are you able to recalibrate them in the controller?

 

[supraguy31]

Im not for sure if you can Actually recalibrate the AEM wideband. If you can then I will try and find out.

 

[IJ.]

Most have a way to do it to allow for slow/old/dying sensors.

 

[supraguy31]

I just pulled out the Manual and it does have a Calibration Knob on the back of the Sensor. Im going to look at mine and make sure its at the correct setting. I will let you know what its set on. Im going to move it for reassurance anyways.

 

[IJ.]

Usually you do what's called a free air calibration.

You hang the sensor on it's wires out of the exhaust awat from any breeze and adjust the knob.

 

[supraguy31]

The manual States from Gas engines, U want it set on P0 or P1. This Sensor doesnt allow free Air calibration from what Im reading. It has a Laser that replaces that.

Straight from the Manual.......
UEGO sensors use a “current pump” to determine the actual oxygen concentration
within the sensing element. The output is in the form of a very small current, which
varies depending on the air-fuel ratio. This is completely different from a narrow band
oxygen sensor, which directly outputs a voltage. The UEGO sensor design allows
measurement of the exact air fuel ratio over the entire operating range.
Each AEM UEGO sensor is individually calibrated and a resistor integral at the
connector body is laser trimmed with this value. This process replaces the traditional
“free air” calibration procedure when changing sensors and implements a sensor
specific calibration for unparalleled accuracy.

 

[MmmBoost]

OK, here is your problem.

Set the Low Throttle point to 74%, and the High Throttle to 75%.

Zero out everything on the Low throttle map.

Tune ONLY on WOT. The TCCS will compensate whenever it is in closed loop. Also known as part throttle, since the ECU goes into enrichment mode (a form of open loop) under WOT. When you lean out the mix, the ECU senses it and makes changes to get it back to normal. Then your WOT mixture is also affected.

I have been running mine like this for several months now, and it held the first tune i did on it. One trick that helps is to use the blue wire (normally for MAF Voltage input) and hook it up to the Vf output pin on the ECU. That way, you can see if the ECU is happy or not just by going into The ETC... Sensor Check option on the SAFC.

Vf:
0 volts: full rich
1 volt: rich
2-3 volts: OK
4 volts: lean
5 volts: full lean

When driving around, this number should stay at 2-3 volts. If not, the ECU IS making changes by itself! The idea is to work with the ECU, still trick it some, but also cooperate at the same time.

Ninja edit: Another tip is don't tune anything on the WOT map when you aren't under boost (1000rpm etc)

 

[Nalleywhacker]

your wideband is way to close to the turbo! in the intructions with the aem uego it says to put it a good 24in away from the turbo. not quite sure if its exactly 24in but i remember its around that i put mine towards the end of my downpipe and it works great!

 

[IJ.]

OK, here is your problem.

Set the Low Throttle point to 74%, and the High Throttle to 75%.

Zero out everything on the Low throttle map.

Tune ONLY on WOT. The TCCS will compensate whenever it is in closed loop. Also known as part throttle, since the ECU goes into enrichment mode (a form of open loop) under WOT. When you lean out the mix, the ECU senses it and makes changes to get it back to normal. Then your WOT mixture is also affected.

I have been running mine like this for several months now, and it held the first tune i did on it. One trick that helps is to use the blue wire (normally for MAF Voltage input) and hook it up to the Vf output pin on the ECU. That way, you can see if the ECU is happy or not just by going into The ETC... Sensor Check option on the SAFC.

Vf:
0 volts: full rich
1 volt: rich
2-3 volts: OK
4 volts: lean
5 volts: full lean

When driving around, this number should stay at 2-3 volts. If not, the ECU IS making changes by itself! The idea is to work with the ECU, still trick it some, but also cooperate at the same time.

Ninja edit: Another tip is don't tune anything on the WOT map when you aren't under boost (1000rpm etc)

This highlights my earlier post about piggybacks fighting the ECU, thanks for posting MmmB.

 

[7MGTEsup]

Yep sensor is to close to the turbo, I'm pretty sure it says in the instructions that on a turbo car it needs to be between 24" - 36" down streem of the turbo outlet. Mine is 2/3's of the way down the the downpipe.

 

[supraguy31]

Thanks all. Heading out to the Exhaust shop today to get another Bung welded in and cap that one off. I will let you all Know what happens.

Robert

 

[Doward]

The LC1 is the only WBO2 I can think of offhand that allows you to do a free-air calibration.

I like the MAFT-Pro/Wideband over the VPC/SAFC, because of the MAFT-Pro's ability to auto-track your AFRs. It'll even provide whatever level of adjustment you tell it to make (up to say... 5% is how I had mine set)

You can also program YOUR engine's VE into the SD conversion tables - does the VPC allow you to do that? You aren't fighting the TCCS with the MAFT-Pro - the TCCS never gets a chance to fight anything - the MAFT-Pro more like 'assimilates' the TCCS LOL

 

[7MGTEsup]

^^^^^^^ Resistance is futile

 

[Buddafucco]

I have the same problem. My sensor is down at the botttom of my down pipe,
so while you should relocate your sensor anyways it isn't going to help your
original problem. On my car (probably yours too) there is no vf reading until
after the car is warmed up & restarted.

 

[supraguy31]

I have the same problem. My sensor is down at the botttom of my down pipe,
so while you should relocate your sensor anyways it isn't going to help your
original problem. On my car (probably yours too) there is no vf reading until
after the car is warmed up & restarted.

So you are saying to relocate the sensor and Buy another Sensor itself wont fix it?

 

[supraguy31]

A weld-in M18 X 1.5 boss is supplied for sensor installation. Mount the O2 sensor in the
exhaust system at least 18 inches downstream from the exhaust port. If you anticipate
high EGT's (over 800C), run a turbocharger, run at high RPM for extended periods of
time or plan on running leaded race fuel then you must mount the sensor at least 36
inches or more downstream of the exhaust port as all of these can cause the sensor to
overheat.

I need to read more often I suppose.

 

[7MGTEsup]

A weld-in M18 X 1.5 boss is supplied for sensor installation. Mount the O2 sensor in the
exhaust system at least 18 inches downstream from the exhaust port. If you anticipate
high EGT's (over 800C), run a turbocharger, run at high RPM for extended periods of
time or plan on running leaded race fuel then you must mount the sensor at least 36
inches or more downstream of the exhaust port as all of these can cause the sensor to
overheat.

I need to read more often I suppose.

If you haven't been running it long and have not been boosing the sensor should still be good. Might have taken a few hours off its life. I don't think replacements are that expensive $60 I think I have seen them for.

Also remember to mount it with at least a 10* angle with the direction of the flow. Its all there in the instructions.

 

[supraguy31]

Yeah, I think they are like $63.00 on a Site that I found. As for running it, I have had a for awhile and when I went to the V-Band Type setup is when I started having this Problem. Again, It being too close to the Exhaust didnt help either. Lesson Learned I suppose. So Im moving it 36" or more Down the Exhaust with a 10* or more angle should clear everything up.

I will let you know what it does once I get it moved, Im also moving the Narrow band O2 sensor down the the Wideband port to get it a little farther down stream.

Here is the website for those who need a Replacement sensor...
http://shopping.lightningmotorsports.com/customer/product.php?productid=1744

Robert

 

[Buddafucco]

Bwest was also dealing with this but he had an innovative wide-band o2, so I
wouldn't say it's an AEM O2 problem.

 

[MmmBoost]

Yes you are right about the sensor mounting location, but thats not what is causing your A/F ratio to bounce around. Once you try and tune like what i explained, then you will see it stabilize out. The o2 sensor should be mounted farther downstream to keep it for a long life.