10 Quick Tips On Audi G28

How to Replace an audi tt key case 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 located on the instrument cluster.

1. Engine Speed Sensor

The grey wire is situated on the edge of transmission, directly above the flywheel ring. The sensor transmits signals through the grey wire to pin T55/49. The ECU then utilizes this information to regulate the flow of fuel, timig and boost. It also sends an alert to the G5 Tachometer in instrument cluster.

The sensor is used to connect with the G40 Camshaft position Sensor. The ecu needs to be aware of when the crankshaft has reached TDC and also the position 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 message. This indicates that the Crank Shaft is out of line with the Intake Camshaft. It could also indicate an issue with the chain or a jumpy chain link in the upper timing chain. The code won't appear without the additional information provided by other sensors (G4 or G40).

Testing can be a bit difficult since there are two connector pins and they perform different functions but the most effective way to test it is to measure resistance between the sensor and the ECU. When the sensor is functional, it should read around 1000 ohms. Look for signs of coolant or oil in the connector bay if you are experiencing problems with this part.

2. Injectors

Yesterday, as i was accelerating off the highway paytoll at a high speed I noticed a significant reduction in power. It was as if the engine had run out of gas. Or my injectors were not firing. In the morning, i removed the spark plugs, 3 were soaked with gazoline and the 4th one was dry. When I start the engine with no sparks, I put a piece of tissue on the top of each of the injector holes, the 3 drenched with gazoline jump out but the 4th one stays shut. I checked the ground connection of ECU pins 14,30, Audi A1 Car Key and 48/55. I found zero ohm. I'm assuming the issue is elsewhere.

I also tried to reset the PID without success. The car will start when the G28 is disconnected, but it is running fine with the G28 plugged in. However the intermittent misfire issue continues to occur at higher RPM. The temperature sensor for the coolant (G62) shows the wrong temperature value of -49c, even if I unplug it. Also i noticed that the oil pressure gauge in the cockpit is showing 2 bar, whereas the actual pressure is 0.0 if i crank up the engine.

I'm not certain what to do, but i feel i have pretty much completely ruled out all other possibilities. But i am afraid I may have missed something. If anyone has any ideas please let me know! TIA!

3. Fuel Pump

The fuel pump in the g28 gets a signal from the RPM sensor. The GM-style transmitter functions similarly to the G4 sender and works on the 80,100,200, UrS, and RS2 vehicles. You can easily find the spare in a salvage shop or parts store. Testing them is easy to do - just put your DMM in resistance mode and measure 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

Our 20vt turbo (3B, AAN, ABY and ADU) engines are equipped with an ECU that has to know the speed and position of the crankshaft to make decisions about timing of the fuel injector, for example. It utilizes a Crank Position Sensor G4 and an Engine Speed Sensor G28 to achieve this. If either of these sensors go bad you will get codes on the diagnostic scanner that can cause the engine to shut down.

A malfunctioning G28 sensor can cause an inaccurate gearbox speed counter and a gearbox which shifts faster than normal, or a misfire in the gear. It is likely that the sensor is failing and needs to be replaced if you experience any of these signs. They're cheap and easy to find especially in the case of a Bosch sensor like ours. If you prefer, GM's version of this part would be a good option.

5. Tachometer

A failing engine sensor could cause a number of problems in your vehicle. It's an essential component of the transmission of your replacement audi car key because it relays information to the ECU about how fast or slow the engine of the car is turning. This sensor can cause the transmission to fail and other components of the car to be affected.

The G5 engine sensor is located near the edge of transmission, above the flywheel ring. It sends a signal via an uncolored wire to the ECU pin T55/49. The ECU utilizes this signal to control the flow of fuel and boost and also to timigrate. It also relays it to the G5 Tachometer located in the instrument cluster. You can check for sensor failure by checking continuity from the sensor to the tachometer. Additionally, you can verify continuity between pin T55/49 of the ECU and pin T6a/1 of the instrument cluster (trace [79trace [79]), and between pin T6a/1 and pin T26a/12. You should detect a resistance of approximately 1000 ohms in these areas. This part is common across the audi replacement key 80-100-200-RS2 model, ranging from the 1985 MC up to the 1997 UrS AN and the 1995 RS2 Du You may also find them in wrecking yards.