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AndrewCologne AndrewCologne is online now
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Join Date: Aug 2015
Location: Cologne / Germany
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Quote:
Originally Posted by Funracer View Post
Quote:
Originally Posted by AndrewCologne
Well, ... then one of the units (ECU vs AEM) does interprete the sensor differently or one of the sensors give different signals at lambda 1.
Or ... if the sensors are installed one on the left side and the other on the right side, then maybe the mixtures/combustions are different on each side, ... but then the reading of the plugs would show it clearly

So ... without going more and more into theoretics ....go to an official emissions check point or service garage with testing equipment and let an official calibrated device do the test. There you can see which one is on spot, .. the ECU or your AEM Controller.
When the O2 sensor is unplugged, the FV goes to 50% as it should. I also have a spare
ECU which has exactly the same readings. Both of these lead me to think the ECU is OK
I already know that both of your original ECUs do give same readings.
But as already mentioned above -> your original ECU(s) and the AEM unit both do read the signal of their sensors differently.

The ECU results in Lambda 1, and the AEM controller system says it's a way off.
To check if the ECU really results in lambda 1, follow PeteKz's advice and with your oscilloscope read pin 2 at the ECU if the voltage signal swings between 0.1 to 0.8 volts – if that is the case, then your ECU behaves as it should and you're on spot with Lambda 1.
Then you should ask yourself why "on the other side" of the engine, the reading is different than Lambda 1, and here the options are a) AEM readings are off, or b) the mixture is different than on the other side of the engine.

Quote:
What do you think of these other readings? All normal? Should Vmax be 6.48V be higher?
As its the test port output, for me its ok
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Old 04-24-2025, 12:43 AM
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