10 Times You ll Have To Be Educated About Audi G28

How to Replace an audi car key case G28 Engine Speed Sensor

Charles the Humble Technician teaches how to replace the G28 Engine Speed Sensor. This sensor is located at the edge of transmission, above the flywheel gear. It transmits a signal to the ECU via an uncolored wire (T55/49), then to the tachometer located in the instrument cluster.

1. Engine Speed Sensor

Located on the edge of the transmission just above the flywheel ring gear G28 Engine Speed Sensor sends an electrical signal to ECU pin T55/49 through a grey wire. The ECU then uses this information to control the flow of fuel, timig and boost. It also sends an indication to the G5 Tachometer in instrument cluster.

The sensor is used to link the G40 Camshaft position Sensor. The ecu needs to know when the crankshaft is TDC and the location of the camshaft so it can start spark and injectors accordingly.

If this sensor fails the ECU will display the P00160 error, which means the Crank Shaft and Intake Camshaft are out of sync and could indicate the chain is stretched or a jump link on the upper chain of timing. The code will not appear without the additional information provided by other sensors (G4 or G40).

It is a little tricky to test as there are different connector pins, and they all have different functions. The best method for doing this is to measure the resistance between the ECU and the sensor. It should read around 1000 ohms if the sensor is in full operation. If you are having problems with this component, look for signs of coolant or oil in the connector bay.

2. Injectors

Yesterday, while accelerating at full speed from the highway paytoll, i experienced an abrupt drop in power like the engine is running out of gas or injectors aren't firing any more. I pulled out the spark plugs this morning, 3 were soaked with gasoline and the fourth was dry. When i crank the engine without sparks, I put a piece of tissue on the top of each hole in the injector and the 3 drenched with gazoline leap out, however the 4th stays shut. I inspected the ground connection on ECU pins 14/55,30/55 and 48/55 i get zero ohm. So i assume the problem is somewhere else.

I also tried to reset PID but without success. The car key cover audi will start if the G28 is not plugged in and is running fine when it is connected, but still has intermittent misfire issues at higher RPM. The coolant sensor (G62), even if it is not plugged in, shows an ice temperature of -49c. Also, i noticed that the gauge for oil pressure in the cockpit shows 2 bar when the actual pressure is 0.0 when i rev the engine.

I'm not sure what to do. I feel like i've pretty much ruled everything else out. I'm afraid 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 function in the 80, 100 200, UrS and RS2 cars which is why you can easily locate one at a junkyard or in a local parts store. It is simple to test them - put your DMM in resistance mode and take measurements between pins 1 (with the bump on the connector's side up) and 2 (2nd from the left on the black connector's side). They should be infinite Ohms.

4. ECU

Our 20vt turbo (3B AAN, ABY and ADU) engines are equipped with an ECU that must know the speed and position of the crankshaft to make decisions about fuel injector timing etc. It uses a Crank Position Sensor G4 and an Engine Speed Sensor G28 to achieve this. If you are experiencing issues with either one of these, the diagnostic scanner will show the codes that could trigger an engine shutdown.

Some of the symptoms of a failing G28 sensor include an inaccurate gearbox rev counter the gears are shifting faster than normal, and/or a misfire when you're in gear. It is probable that the sensor is failing and requires to be replaced if you notice any of these symptoms. They're cheap and easy to find particularly in the case of a Bosch sensor like ours. Alternatively, the GM version of this unit is also a great option.

5. Tachometer

A failing engine speed sensor could be the cause of many issues in your car. It's a crucial component of the transmission in your Replacement audi a3 Key since it sends information to the ECU regarding how fast or slowly the engine is turning. This sensor Audikey could cause the transmission to fail and other components of the car to be affected.

The G5 engine speed sensor is located on the outside of the transmission just above the flywheel ring gear. It transmits a signal to the ECU at pin T55/49, via an uncolored wire. The ECU is then able to process this signal to regulate fuel, timig, and boost, and also transmitting it to the G5 tachometer in the instrument cluster. You can test the sensor for failure by examining the continuity between it and the tachometer, between the ECU pin T55/49 and the instrument cluster connection to pin T6a/1 (trace [79]) and between T6a/1 and the instrument cluster pin T26a/12. You should see approximately 1000 ohms of resistance between those points. This is the same across the audi a3 key fob replacement 80-100-200-RS2 range, from the 1985 MC up to the 1997 UrS An and 1995 RS2 DU You may also find good ones in wrecking yards.