Quote:
Originally Posted by Mkl  I guess all the O2 sensors are 4 wired. 2 for power supply, 1 for ground and 1 for DME. From my understanding the emulator O2 and DME come together with the O2 DME wire. Is that right? |
That is correct. The simulator is a pass-through devise unless active so it passes the exact O2 reading to the DME when in the off position. When it is active it removes the O2 signal to the DME and sends a lean condition signal which is what the DME looks for to check air pump operation.
The air pump injects air in the exhaust so to simulate the air pump you just create a lean condition reading from the O2 and the DME thinks it has the air pump working correctly adding additional fresh air to the exhaust to help heat up the cat converter quicker.
The simulator is only on for 30 seconds to 1 minute when you cold start the car then the DME switches it off and it's like the simulator was not even installed on the car.
Hope this helps, John S