The 3 Greatest Moments In Audi G28 History

How to Replace an audi tt replacement key G28 Engine Speed Sensor

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

1. Engine Speed Sensor

It is located on the outside of the transmission above the flywheel ring gear, the G28 Engine Speed Sensor sends an electrical signal to ECU pin T55/49 through the grey wire. The ECU uses this information to control boost and fuel. It also sends signals to the G5 tachometer in the instrument cluster.

The sensor serves as a reference for comparing with the G40 Camshaft Position Sensor. The ecu must know when the crankshaft reached TDC and also the location of the camshaft so that it can activate the spark and injectors.

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

Testing can be a bit difficult as there are two different pins for the connector and they perform different functions however the best way to test it is to measure resistance between the sensor and the ECU. It should read approximately 1000 ohms if the sensor is at full operation. Examine for signs of coolant, or oil in the connector bay if you have issues with this part.

2. Injectors

Yesterday, while accelerating at full speed from the highway paytoll, I experienced a big cut in power like the engine is out of gas or the injectors aren't firing at all. In the morning, i removed the spark plugs, three were soaked with gazoline and the 4th one was dry. I put a piece of tissue over each hole in the injector and when I start the engine without sparks, the ones with gazoline jump right out. The 4th one stays closed. I tried to test the ground connections of ECU pins 14,30, and 48/55. I found zero ohm. Therefore, i think the issue is in another place.

I also tried to reset the PID but with no luck. The car is able to start if the G28 is disconnected and it runs perfectly when it is plugged in however it has the intermittent misfire issue at higher RPM. The coolant sensor (G62), even when it is unplugged, shows an ice temperature of -49c. I also noticed that the oil gauge in the cockpit shows 2 bars when the actual pressure is 0.

I'm not sure what to do. I think I've ruled everything else out. I'm concerned that i may have missed something. Let me know should 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 sensor is identical to the G4 and both are used in the 80 100 200, UrS and RS2 cars which is why you can easily locate one at a wrecking yard or in a local parts store. It is easy to test them - simply put your DMM into resistance mode and determine the distance between pins 1 and 2 (with the bump at the connector's end facing up). They should be infinite Ohms.

4. ECU

Our 20vt turbo (3B AAN, ABY and ADU) engines are equipped with an ECU that needs to know the position and speed of the crankshaft in order to make a decision about timing of the fuel injectors, etc. It makes use of a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If either of these sensors go bad you will get codes on the diagnostic scanner which can cause the engine to shut down.

Some of the symptoms of a failed G28 sensor are an inaccurate gearbox rev counter and gears that shift faster than normal and/or misfiring when you're in gear. It is likely that the sensor is failing and requires to be replaced if you encounter any of these signs. They are cheap and easy-to-find particularly if they're a Bosch unit like ours. Alternately, the GM version of this part is also a good option.

5. Tachometer

A damaged engine sensor could cause a myriad of issues within your vehicle. It is an important part of the transmission of your audi a3 keys smart Key replacement - http://douerdun.com,, as it transmits information to the ECU on how fast or slowly the car's engine is spinning. This sensor can cause the transmission to fail 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. It sends a signal directly to the ECU at pin T55/49 through a grey wire. The ECU then uses and processes this signal to regulate fuel, timig, and boost, and also transmitting it to the G5 tachometer inside the instrument cluster. You can check the sensor for failure by examining the continuity between it and the tachometer, between ECU pin T55/49 and the instrument cluster connection via pin T6a/1 (trace [79]) and between pin T6a/1 and the instrument cluster pin T26a/12. You should see the resistance to be around 1000 ohms between these two points. This is a standard part that is found across the audi q7 key 80, 100 200, UrS and RS2 range from 1985 MC until the 1997 UrS AAN and 1995 RS2 ADU so good ones could be available in wrecking yards.