"Ask Me Anything:10 Responses To Your Questions About Audi G28

How to Replace an audi replacement key G28 Engine Speed Sensor

In this video, Charles the Humble Mechanic shows how to replace the G28 engine speed sensor. This sensor is located on the edge of the transmission just above the flywheel ring gear. It transmits a signal to the ECU via an uncolored wire (T55/49) which is then sent to the tachometer located in the instrument cluster.

1. Engine Speed Sensor

The sensor is located at the edge of the transmission just above the flywheel ring gear, the G28 Engine Speed Sensor sends signals to ECU pin T55/49 via a grey wire. The ECU uses this information to regulate fuel and boost. It also sends an indication to the G5 tachometer in the instrument cluster.

The sensor is used as a reference to correlate with 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 in the right way.

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 be a sign of a chain stretch or a jumped chain link in the upper 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 because there are two connector pins, and they perform different functions but the best method to test it is to measure resistance between the sensor and the ECU. It should read approximately 1000 ohms if the sensor is operating at its maximum. If you're experiencing issues with this component, look for signs of coolant or oil in the connector bay.

2. Injectors

Yesterday accelerating full speed from highway paytoll i had massive power loss like the engine is out of gas or injectors are not firing at all. In the morning, i removed the spark plugs, 3 were soaked with gazoline and the 4th one was dry. When i crank the engine with no sparks, I put a piece of tissue on the top of each hole in the injector and the 3 that were drenched in gazoline jump out but the 4th stay shut. I checked the ground connection on ECU pins 14/55,30/55 and 48/55 I got zero Ohm. I'm assuming that the issue is in another location.

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

I'm not sure what to do, as i think i've pretty much eliminated everything else. I'm afraid i may have missed something. Let me know If you have any suggestions! 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 functions similarly to the G4 sender, and both operate 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 easy to test them - simply switch your DMM into resistance mode and measure the distance between pins 1 and 2 (with the bump on the connector's edge facing up). They should be infinite ohms.

4. ECU

The ECU in our 20vt turbo (3B AAN ABY ADU) engines must know the position and speed of the crankshaft to determine timing of the fuel injector, etc. In order to do this it makes use of a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If you have a problem with either one of these, the diagnostic scanner will show codes that could cause an engine shut down.

A malfunctioning G28 sensor could cause an inaccurate speed counter for the gearbox and a gearbox which shifts more quickly than normal, and/or a misfire in gear. It is possible that the sensor is failing and needs to be replaced if you encounter any of these signs. They're cheap and easy to find particularly in the case of a Bosch unit like ours. Alternately, the GM version of this component is also a good choice.

5. Tachometer

A failing engine speed sensor could be the reason behind many issues with your car. It's an essential component of the audi spare key new audi tt key replacement (Read A lot more)'s transmission since it relays information to the ECU about how fast or slow the vehicle's crankshaft is spinning. If this sensor fails, it can disrupt the performance of the transmission and the other car's components.

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, via an uncolored wire. The ECU uses this signal to control the flow of fuel and boost and also to timigrate. It also transmits it to the G5 Tachometer in instrument cluster. You can determine if the sensor is in failure by examining the continuity from the sensor to the tachometer. You can also examine the continuity between pins T55/49 of the ECU and pin T6a/1 of the instrument cluster (trace [79]), and between pin T6a/1 as well as pin T26a/12. You should see an average resistance of 1000 ohms between these points. This is the same across the audi tt key case 80-100-200-RS2 model, ranging from the 1985 MC up to the 1997 UrS AN and 1995 RS2 DU So, you may find good ones in wrecking yards.