How to Replace an audi a3 key fob replacement G28 Engine Speed Sensor

Charles the Humble Technician teaches you how to replace the G28 Engine Speed Sensor. This sensor is located on the outside of the transmission, above the flywheel gear. It sends a signal to the ECU via a grey wire (T55/49) and then to the tachometer within the instrument cluster.

1. Engine Speed Sensor

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

The sensor serves as a reference for Car Key Cover Audi comparing 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 throw the P00160 error, which means the Crank Shaft and Intake Camshaft are out of sync, possibly indicating the chain is stretched or a jump link on the upper chain of timing. The code won't appear without the additional information supplied by other sensors (G4 or G40).

Testing is a bit tricky since there are two pins for the connector and they serve different purposes but the most effective way to test it is to measure resistance between the sensor and the ECU. When the sensor is operational, it should read about 1000 ohms. If you're having issues with this sensor, look for evidence of oil or coolant in the connector bay.

2. Injectors

Yesterday, as i was accelerating off the highway paytoll at full speed I noticed a massive drop in power. It was like the engine was running out of gas. Or, my injectors were not firing. This morning i pull out the spark plugs. Three were drenched in gazoline, the 4th one was dry. I placed a tissue over each hole in the injector and when I start the engine without sparks, the three with gazoline jump right out. The 4th one stays closed. I tested the ground connection on ECU pins 14/55, 30/55 and 48/55. I get zero Ohm. So i assume the problem is somewhere else.

I also tried to reset PID without success. The car will start when the G28 is unplugged, and it is running fine with the G28 connected. However the intermittent misfire issue still occurs at higher RPM. The coolant sensor (G62) even when it is unplugged, shows temperatures of -49c. Also, i noticed that the gauge for oil pressure in the cockpit shows 2 bar when the actual pressure is 0.0 when I crank up the engine.

I'm not sure what to do, but i think i've pretty much ruled out everything else. But i'm worried that I may have missed something. Please let me know If you have any suggestions! TIA!

3. Fuel Pump

The fuel pump in the g28 can be activated by a signal from the RPM sensor. The GM-style sender is the same as the G4 and both function in the 80, 100, 200, UrS and RS2 cars so you can easily find one at a wrecking yard or from a parts store. It is simple to test them - put your DMM in resistance mode and measure between pins 1 (with the bump on the connector's end up) and 2 (2nd from 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 needs to be aware of the speed and position of the crankshaft in order to make decisions regarding fuel injector timing etc. It uses a Crank Position Sensor G4 and an Engine Speed Sensor G28 to achieve this. If you encounter a problem with either of these sensors, the diagnostic scanner will display codes that could cause an engine shut down.

The signs of a failing G28 sensor are an inaccurate rev counter for the gearbox the gears are shifting faster than normal and/or misfiring when you're in gear. If you experience any of these problems, it is likely your sensor is failing and requires replacement audi a3 key. They're cheap and easy to find particularly in the case of a Bosch model like ours. Alternatively, the GM version of this unit is also a good option.

5. Tachometer

A malfunctioning engine speed sensor could be the cause of a slew of issues in your car. It is a crucial part of the audi key replacement cost's transmission as it sends information to the ECU about how the car key Cover audi's crankshaft is turning. This sensor can cause the transmission to fail and other components in the car to be affected.

The G5 engine sensor is located at the outskirts of the transmission, car key cover Audi just above the flywheel ring. It sends signals via gray wire to ECU pin T55/49. The ECU is then able to process this signal to control fuel, timig and boost as well as sends it on to the G5 Tachometer located in the instrument cluster. You can check the sensor for any failure by checking the continuity between it and the tachometer. You can also check continuity between ECU pin T55/49 and the instrument cluster connection on pin T6a/1 (trace [79]) and between T6a/1 and the instrument cluster pin T26a/12. It should show around 1000 ohms of resistance between these two points. This is a common part across the audi key fob not working 80 100 200, UrS and RS2 range from 1985 MC to the 1997 UrS AAN and 1995 RS2 ADU, so the best ones might be availble in wrecking yards.