Why Nobody Cares About Audi G28
How to Replace an Audi G28 Engine Speed Sensor
In this video, Charles the humble mechanic demonstrates how to replace the G28 engine speed sensor. This sensor is situated on the outside of the transmission over the flywheel gear. It sends a signal to the ECU via the grey wire (T55/49), then to the tachometer in the instrument cluster.
1. Engine Speed Sensor
The grey wire is situated on the edge of transmission, directly above the flywheel ring. This sensor sends a signal via 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 indicator to the G5 Tachometer located in the instrument cluster.
The sensor serves as a reference to correlate 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, the ECU will display 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. However, the error code won't appear on its own without additional information from other sensors (G4 and G40).
It's a bit tricky to test as there are different pins on the connector and each one has different functions. The most effective method to test it is by measuring the resistance between the ECU and the sensor. It should read about 1000 ohms when the sensor is operating at its maximum. Check for evidence of coolant or oil in the connector bay if there are issues with this component.
2. Injectors
Yesterday, while accelerating at full speed from the highway paytoll, i experienced a big cut in power like the engine is out of gas or the injectors are not firing at all. I pulled out the spark plugs this morning and found that 3 were drenched in gasoline and the fourth was unclean. I put tissue over each injector hole and when I start the engine without sparks, the 3 that have gazoline pop right out. The 4th one stays closed. I checked the ground connection of ECU pins 14,30 and 48/55. I found zero ohm. I'm assuming the issue is in another place.
I also tried to reset the PID but without success. The car is able to start if the G28 is not plugged in and it runs perfectly when it is plugged in but it still has intermittent misfire issues at higher RPM. The coolant sensor (G62) even when unplugged, still shows a temperature of -49c. Also, i noticed that the oil pressure gauge in the cockpit is showing 2 bar, whereas the actual pressure is 0.0 when i rev the engine.
I'm not sure what to do, as i believe that i've eliminated everything else. I'm concerned that i may have missed something. Let me know if you have any ideas! TIA!
3. Fuel Pump
The fuel pump of the g28 receives signals 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 locate the spare in a salvage shop or a parts store. It is simple to test them: simply put your DMM into resistance mode and determine the distance between pins 1 and 2 (with the bump at the connector's end facing upwards). They must be infinite Ohms.
4. ECU
Our 20vt turbo (3B AAN, ABY, and ADU) engines have an ECU that must know the position and speed of the crankshaft in order to make decisions about timing of the fuel injector, for example. It makes use of a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If either of these go bad you will get codes on the diagnostic scanner which can lead to engine shutdown.
The signs of a failed G28 sensor are an inaccurate rev counter for the gearbox the gears are shifting faster than normal, and/or a misfire when you're in gear. It is likely that your sensor is failing and needs to be replaced if you experience any of these symptoms. They're cheap and easy to find particularly in the case of a Bosch sensor like ours. You can also choose the GM version of this part is also a good choice.
5. Tachometer
A malfunctioning engine sensor can cause a myriad of issues in your vehicle. It's a crucial component of the transmission of your programming audi replacement key replacement key for audi a3 (lzdsxxb.com), as it transmits information to the ECU on how fast or slowly the car's engine is turning. This sensor 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 and transmits a signal to the ECU at pin T55/49 through a grey wire. The ECU utilizes this signal to regulate the flow of fuel and boost and also to timigrate. It also sends it to the G5 Tachometer located in the instrument cluster. You can determine if the sensor is in failure by examining the continuity from the sensor to the tachometer. Also, you can check continuity between pin T55/49 of the ECU and pin T6a/1 of the instrument cluster (trace [79]) and between pin T6a/1 and pin T26a/12. You should see around 1000 ohms of resistance between those two pins. This is a common component across the audi car key holder 80 100 200, UrS and RS2 range from 1985 MC to the 1997 UrS AAN and 1995 RS2 ADU so good ones could be available in wrecking yards.