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

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How to Replace an audi keys G28 Engine Speed Sensor

Charles the Humble Technician shows you how to replace audi key the G28 Engine Speed Sensor. This sensor is situated at the edge of transmission just above the flywheel gear. It transmits a signal to the ECU via a grey wire T55/49, then to the tachometer located on the instrument cluster.

1. Engine Speed Sensor

The grey wire is located on the edge of transmission, above the flywheel ring. The sensor transmits an electrical signal through the grey wire to pin T55/49. The ECU then uses this information to control the boost, fuel, and timig. It also sends signals to the G5 tachometer inside the instrument cluster.

The sensor is used to connect the G40 Camshaft position Sensor. The ecu must know when the crankshaft is TDC and Audi Keyless Entry - Maps.Google.Com.Ua - the location of the camshaft so it can start spark and injectors according to the situation.

If this sensor fails, the ECU will throw the P00160 error, which means the Crank Shaft and Intake Camshaft are not in sync and possibly indicating the chain stretching or a jump link on the upper chain of timing. However, the error code won't appear on its own, without additional information from other sensors (G4 and G40).

It can be a bit difficult to test since there are different connector pins, 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 approximately 1000 ohms when it is at full operation. Examine for signs of coolant, or oil in the connector bay if you have issues with this component.

2. Injectors

Yesterday accelerating full speed from highway paytoll, I experienced an abrupt drop in power like the engine is out of gas or injectors are not firing anymore. In the morning, i removed the spark plugs, three were drenched in gazoline, the fourth was dry. When i crank the engine, there are no sparks i put tissue on the top of each hole in the injector, the 3 drenched with gazoline pop out, but the 4th one stays shut. I checked the ground connection of ECU pins 14,30 and 48/55. I found 0ohm. So i assume the problem is in another place.

I also tried to reset the PID without success. The car is able to start if the G28 is unplugged and runs fine when it is plugged in but it still has the intermittent misfire issue at higher RPM. The coolant sensor (G62) even when it is unplugged, shows an ice temperature of -49c. Also i noticed that the gauge for oil pressure in the cockpit shows 2 bar, whereas the actual pressure is 0.0 when I crank up the engine.

I don't know what to do. I feel like i've pretty much all other possibilities out. But i am afraid I might have missed something. If anyone has any suggestions, please share them! TIA!

3. Fuel Pump

The fuel pump in the g28 can be activated by a signal from the RPM sensor. The GM-style transmitter is similar to the G4 sender and both work on the 80,100,200, UrS, and RS2 vehicles. You can easily locate an extra in a wrecking shop or a parts store. Test them out by putting your DMM in resistance mode and measure the resistance between pins 1 (with the bump on the connector end up) and 2 (2nd from left on the black connector's side). They should be infinite Ohms.

4. ECU

Our 20vt turbo (3B, AAN, ABY and ADU) engines are equipped with an ECU that needs to know the position and speed of the crankshaft to make decisions about fuel injector timing etc. To do this, it uses a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If you encounter a problem with either one of these, the diagnostic scanner will display codes that could lead to the engine shutting down.

Some of the symptoms of a malfunctioning G28 sensor are an inaccurate gearbox rev counter, gears shifting quicker than normal and/or a misfire when you are in gear. If you experience any of these problems, it is likely your sensor is deteriorating and should be replaced. The good news is they are quite affordable and easy to find, especially in the case of an Bosch unit which is what ours are. Alternatively, the GM version of this part is also a good option.

5. Tachometer

A failing engine speed sensor could be a cause for numerous issues with your vehicle. It's a crucial component of the transmission of your Audi New Key because it relays information to the ECU regarding how fast or slow the engine is turning. If the sensor fails, it could disrupt the performance of the transmission as well as the other car's components.

The G5 engine speed sensor is situated on the edge of the transmission, above the flywheel ring gear. It sends a signal directly to the ECU at pin T55/49, via a grey wire. The ECU utilizes this signal to regulate fuel and boost, and also timig. It also relays it to the G5 Tachometer located in the instrument cluster. You can test for sensor failure by examining the continuity from the sensor to the tachometer. Additionally, you can check continuity between pin T55/49 of the ECU and pin T6a/1 of the instrument cluster (trace [79trace [79]), and between pin T6a/1 as well as pin T26a/12. You should see an average resistance of 1000 ohms between these two points. This is the same across the audi q7 key 80-100-200-RS2 series, starting from the 1985 MC all the way up to the 1997 UrS AN and the 1995 RS2 DU You may also find some good ones in wrecking yards.