Why No One Cares About Audi G28

How to Replace an Audi Keys Replacement Cost 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, above the flywheel gear. It sends a message to the ECU via a grey wire T55/49, then to the tachometer 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 a signal to ECU pin T55/49 through an uncolored wire. The ECU uses this information to control fuel and boost. It also sends signals to the G5 Tachometer located in the instrument cluster.

The sensor is used to link with the G40 Camshaft position Sensor. The ecu must know when the crankshaft is TDC and the location of the camshaft so it can trigger spark and injectors in the right way.

If this sensor fails, the ECU will display the P00160 error, which means the Crank Shaft and Intake Camshaft aren't in sync and possibly indicating chain stretch or a jumped link on the upper chain of timing. However, the error code won't be displayed on its own without additional information from other sensors (G4 and G40).

Testing is a bit challenging as there are two different connector pins, and they perform different functions however the best method to test it is to measure the resistance between the sensor and the ECU. When the sensor is fully operational, it should be reading around 1000 ohms. If you're having issues with this component, look for audi replacement key Cost Uk signs of oil or coolant in the connector bay.

2. Injectors

Yesterday, while accelerating at full speed from the highway paytoll, I experienced massive power loss like the engine is out of gas or injectors are not firing anymore. I pulled out the spark plugs this morning, 3 were soaked with gasoline and the fourth was unclean. When I start the engine, there are no sparks, I put a piece of tissue on the top of each hole in the injector, the 3 drenched with gazoline jump out but the 4th stays shut. I tested the ground connection on ECU pins 14/55, 30/55 and 48/55. I got zero ohm. I'm assuming that the issue is somewhere else.

I also tried to reset PID without success. The car is able to start when the G28 is not plugged in and runs fine when it is connected but it still is experiencing intermittent misfires at higher RPM. The coolant sensor (G62) even if it is not plugged in, shows a temperature of -49c. I also noticed that the oil gauge in the cockpit shows 2 bars but the actual pressure is zero.

I'm not sure what to do, but i believe that i've eliminated everything else. But i'm worried that I might have missed something. Let me know If you have any suggestions! TIA!

3. Fuel Pump

The fuel pump on the g28 is activated by a signal sent 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. It is easy to find an extra in a wrecking shop or parts store. It is simple to test them - just put your DMM into resistance mode and measure the distance between pins 1 and 2 (with the bump on the connector's edge facing upwards). They should be infinite Ohms.

4. ECU

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

The signs of a failed G28 sensor include an inaccurate rev counter for the gearbox and gears that shift 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 news is that they are quite affordable and easy to find, especially if you're looking at an Bosch unit which is what we have. Alternately, the GM version of this component is also a good choice.

5. Tachometer

A damaged engine sensor could cause a variety of issues within your vehicle. It's an essential component of the audi key shell's transmission as it sends information to the ECU about how fast or slow the car's crankshaft is turning. If this sensor fails, it can affect the performance of the transmission, as well as the other car's components.

The G5 engine sensor is located at the edge of the transmission, over the flywheel ring. It sends a signal via gray wire to ECU pin T55/49. The ECU utilizes this signal to regulate the flow of fuel and boost and also to timigrate. It also transmits it to the G5 Tachometer inside the instrument cluster. You can check the sensor for any failure by checking the continuity between it and the tachometer, between the ECU pin T55/49 and the instrument cluster connection to pin T6a/1 (trace [79]) and between pin T6a/1 and the instrument cluster pin T26a/12. You should see the resistance to be around 1000 ohms between these points. This part is common across the audi a3 key replacement 80-100-200-RS2 series, starting from the 1985 MC up to the 1997 UrS An and 1995 RS2 Du So, you may find good ones in wrecking yards.