10 Reasons You ll Need To Learn About Audi G28

How to Replace an audi remote key 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 outside of the transmission just above the flywheel gear. It transmits a signal to the ECU through the grey wire T55/49 and 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 G28 Engine Speed Sensor sends a signal to ECU pin T55/49 through the grey wire. The ECU utilizes this information to regulate the amount of fuel and boost. It also sends an alert to the G5 Tachometer located in the instrument cluster.

The sensor is used as a reference point to connect with the G40 Camshaft Position Sensor. The ecu has to know when the crankshaft has reached TDC and also the position of the camshaft, to trigger the spark and injectors.

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

Testing is a bit tricky since there are two connector pins and they have different functions but the best method to test it is by measuring resistance between the sensor and the ECU. It should read about 1000 ohms if the sensor is in full operation. Check for signs of coolant or audi Tt key (menwiki.men) oil in the connector bay if you are experiencing issues with this component.

2. Injectors

Yesterday, when i was accelerating to the fullest speed from highway paytoll, i experienced a big cut in power like the engine is running out of gas or injectors aren't firing at all. Today, i pulled out the spark plugs, 3 were drenched in gazoline, the fourth one was dry. I placed a tissue over each hole in the injector and when i start the engine without sparks, the three with gazoline jump right out. The 4th one remains closed. I tested the ground connection on ECU pins 14/55, 30/55 and 48/55. i get 0ohm. Therefore, i think the issue is somewhere else.

I also tried to reset PID but without success. The car will start when the G28 is disconnected and runs fine when it is connected, but still has intermittent misfire issues at higher RPM. The coolant sensor (G62) even when unplugged, still shows temperatures of -49c. I also noticed that the oil gauge in the cockpit shows 2 bars but the actual pressure is zero.

I'm not certain what to do, i think i've pretty much completely ruled out all other possibilities. I'm worried that i might have missed something. If anyone has suggestions, please share them! TIA!

3. Fuel Pump

The fuel pump in the g28 can be activated by a signal sent from the RPM sensor. The GM-style transmitter is similar to the G4 sender and works on the 80,100,200, UrS, and RS2 vehicles. It is easy to find a spare in a wrecking shop or parts store. It is simple to test them by putting your DMM in resistance mode and measure between pins 1 (with the bump on the connector end up) and 2 (2nd from left on the black connector's side). They should be infinite Ohms.

4. ECU

The ECU of our 20vt turbo (3B AAN ABY ADU) engines needs to know both the position and speed the crankshaft to make decisions regarding timing of the fuel injector, etc. To accomplish this, it makes use of a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If either of these sensors go wrong, you will receive codes on the diagnostic scanner which can lead to engine shutdown.

The signs of a failing G28 sensor are an inaccurate rev counter for the gearbox and gears that shift faster than normal and/or misfiring when you are in gear. It is possible that the sensor is failing and needs to be replaced if you encounter any of these symptoms. They're inexpensive and easy to locate particularly in the case of an Bosch unit like ours. You can also choose the GM version of this part is also a good option.

5. Tachometer

A malfunctioning engine speed sensor could be the reason behind a slew of issues with your car. It's a vital component of your audi connect key's transmission, since it relays information to the ECU about how the car's crankshaft is spinning. When this sensor fails, it will affect the performance of the transmission and the rest of the car's components.

The G5 engine sensor is located near the edge of the transmission, just above the flywheel ring. It sends a signal via an uncolored wire to the ECU pin T55/49. The ECU uses this signal to regulate the amount of fuel and boost, and also to timigrate. It also transmits it to the G5 Tachometer in instrument cluster. You can check the sensor for failure by checking continuity between it and the tachometer. You can also check continuity between ECU pin T55/49 and the instrument cluster connection via pin T6a/1 (trace [79]) and between T6a/1 and the instrument cluster pin T26a/12. It should show approximately 1000 ohms resistance between these two points. This is a standard part across the audi tt replacement key 80, 100, 200, UrS and RS2 range from 1985 MC through the 1997 UrS AAN and 1995 RS2 ADU so good ones might be availble in wrecking yards.