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

How to Replace an new audi 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 at the top of the transmission just above the flywheel ring gear. It transmits a signal the ECU via the grey wire (T55/49) and then to the tachometer in the instrument cluster.

1. Engine Speed Sensor

Located on the edge of the transmission, above the flywheel ring gear the G28 Engine Speed Sensor sends a signal to ECU pin T55/49 via the grey wire. The ECU then utilizes this information to regulate the boost, fuel, and timig. It also sends an indication to the G5 Tachometer within the instrument cluster.

The sensor serves as a reference point to connect with the G40 Camshaft Position Sensor. The ecu needs to know when the crankshaft reached TDC and also where the camshaft lies so that it can activate the spark and injectors.

If this sensor fails the ECU will show the P00160 error, which means the Crank Shaft and Intake Camshaft aren't in sync and could indicate the chain stretching or a jump link on the upper timing chain. The code won't appear without the additional information supplied by other sensors (G4 or G40).

It can be a bit difficult to test since there are several pins on the connector, and each has its own functions. The best method for doing this is by measuring the resistance between the ECU and the sensor. When the sensor is functional, Audi Key Fob (Full Article) it should read around 1000 ohms. If you're having issues with this sensor, look for signs of coolant or oil in the connector bay.

2. Injectors

Yesterday, while accelerating from the highway paytoll at full speed I noticed a massive reduction in power. It was like the engine had run out of gas. Or, my injectors weren't firing. This morning i pull out the spark plugs, three were drenched in gazoline, the 4th one was dry. When i crank the engine with no sparks, i place a tissue on top of each injector hole and the 3 that were drenched in gazoline pop out, but the 4th one stays shut. I checked the ground connection on ECU pins 14/55, 30/55 and 48/55. i get zero ohm. I'm assuming the issue is somewhere else.

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 connected. However the intermittent misfire issue persists at higher RPM. The coolant sensor (G62) even when unplugged, still shows temperatures of -49c. Also, i noticed that the oil pressure gauge in the cockpit shows 2 bar when the actual pressure is 0.0 when i rev the engine.

I'm not certain what to do, but i think i've pretty much eliminated everything else. But i am afraid I might have missed something. If anyone has any suggestions, please let me know! TIA!

3. Fuel Pump

The fuel pump in the g28 receives a signal from the RPM sensor. The GM-style transmitter is the same as the G4 and both are used in the 80 100, 200, UrS and RS2 cars so you can easily find one at a junkyard or in a local parts store. It is easy to test them: simply switch your DMM into resistance mode and test the distance between pins 1 and 2 (with the bump at the connector end facing up). They must be infinite ohms.

4. ECU

The ECU of our 20vt turbo (3B AAN ABY ADU) engines must know both the position and speed of the crankshaft to make decisions regarding fuel injector timing, etc. It utilizes a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If either of these goes badly, you will see codes on the diagnostic scanner that can lead to engine shutdown.

Some of the signs 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 possible that the sensor is failing and needs to be replaced if you encounter any of these signs. The good thing is that they are very cheap and easy to find particularly if you're looking at the Bosch model, like ours. You can also choose the GM version of this component is also a great option.

5. Tachometer

A malfunctioning engine sensor can cause a myriad of issues in your car. It's a crucial component of the transmission in your audi replacement key service, as it transmits information to the ECU about how fast or slowly the engine is spinning. If this sensor fails, it could disrupt the performance of the transmission, as well as the rest of the car's components.

The G5 engine sensor is located near the edge of the transmission, over the flywheel ring. It transmits an electrical signal through gray wire to ECU pin T55/49. The ECU then processes this signal to control fuel, timig and boost, and also transmitting it to the G5 tachometer in the 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 [79trace [79]) as well as between T6a/1, and the instrument cluster pin T26a/12. You should detect a resistance of approximately 1000 ohms in these areas. This is a typical part that is found across the audi smart key replacement replacement audi a3 key key cost (Read More At this website) 80 100 200, UrS and RS2 range from 1985 MC to the 1997 UrS AAN and 1995 RS2 ADU so good ones might be availble in wrecking yards.