How to Replace an replacement key audi G28 Engine Speed Sensor

In this video Charles the humble mechanic demonstrates how to replace the G28 engine speed sensor. The sensor is located on the edge of the transmission, above the flywheel ring gear. It transmits a signal to the ECU via the grey wire T55/49 and then to the tachometer in the instrument cluster.

1. Engine Speed Sensor

The grey wire is located at the edges of the transmission, directly above the flywheel ring. This sensor sends signals through the grey wire to pin T55/49. The ECU utilizes this information to regulate boost and fuel. It also sends an indicator to the G5 Tachometer within the instrument cluster.

The sensor is used to connect the G40 Camshaft position Sensor. The ecu must know when the crankshaft is TDC and where the camshaft is located so that it can activate spark and injectors according to the situation.

If this sensor fails to function, the ECU will display a P00160 error code. This means that the Crank Shaft is out of line with the Intake Camshaft. It could also indicate the possibility of a chain stretch or jumpy chain link in the upper timing chain. However, the error code won’t be displayed on its own without additional information from other sensors (G4 and G40).

It is a little tricky to test because there are different connector pins, and they all have different functions. The most effective method to test it is by measuring the resistance between the ECU and the sensor. If the sensor is operational, it should be reading about 1000 ohms. Examine for evidence of coolant or oil in the connector bay if there are problems with this part.

2. Injectors

Yesterday, as i was accelerating off the highway paytoll at full speed I noticed a significant reduction in power. It was as if the engine had run out of gas. Or, my injectors weren’t firing. I took out the spark plugs this morning, 3 were drenched in gasoline and the 4th was dry. I placed a tissue over each injector hole, and when i turn the engine on without sparks, the 3 that have gazoline pop right out. The fourth one remains shut. I checked the ground connection of ECU pins 14,30, and 48/55. I got zero ohm. I think the issue is elsewhere.

I also tried to reset the PID without success. The car will start when the G28 is unplugged, and it runs fine with the G28 plugged in. However the intermittent misfire issue still occurs at higher RPM. The coolant sensor (G62), even when it is unplugged, shows a temperature of -49c. I also noticed that the oil gauge in the cockpit shows 2 bars while the actual pressure is 0.

I’m not certain what to do, as i believe that i’ve ruled out everything else. I’m worried that i might have missed something. Please let me know If you have any suggestions! TIA!

3. Fuel Pump

The fuel pump on the g28 is activated by a signal from the RPM sensor. The GM-style transmitter is identical to the G4 sender and both work on the 80,100,200, UrS, and RS2 vehicles. You can easily locate an extra in a wrecking shop or parts store. Test them out – put your DMM in resistance mode and take measurements between pins 1 (with the bump on the connector’s end up) and 2 (2nd from the left on the black end of the connector). They must be infinite Ohms.

4. ECU

The ECU in our 20vt turbo (3B AAN ABY ADU) engines needs to know the position and speed the crankshaft to determine fuel injector timing, etc. It utilizes a Crank Position Sensor G4 and an Engine Speed Sensor G28 to achieve this. If you encounter a problem with either one of these, the diagnostic scanner will display codes that could lead to an engine shutdown.

A failing G28 sensor can cause an inaccurate speed counter for the gearbox or a gearbox that shifts faster than normal, or a misfire while in the gear. It is likely that the sensor is failing and requires to be replaced if you experience any of these signs. They are cheap and easy-to-find, especially when they’re an Bosch unit like ours. Alternately, GM’s version this component is an excellent choice.

5. Tachometer

A damaged engine sensor could cause a myriad of issues in your audi car keys replacement. It is a crucial part of the Audi Keyless Go‘s transmission because it communicates to the ECU about how the car’s crankshaft is turning. This sensor remote could cause the transmission to malfunction and other components of the car to be affected.

The G5 engine speed sensor is located on the edge of the transmission, above the flywheel ring gear and transmits a signal to the ECU at pin T55/49, via a grey wire. The ECU then processes this signal to control fuel, timig and boost, and also transmitting it to the G5 tachometer in the instrument cluster. You can test the sensor for any failure by checking the continuity between it and the tachometer. You can also check continuity between ECU pin T55/49 and the instrument cluster connection on pin T6a/1 (trace [79]) and between pin T6a/1 and the instrument cluster pin T26a/12. You should detect the resistance to be around 1000 ohms between these points. This is a typical part that is found across the audi new key 80 100 200, UrS and RS2 range from 1985 MC to the 1997 UrS AAN and 1995 RS2 ADU. Good ones could be available in wrecking yards.