The Most Pervasive Problems With Audi G28

How to Replace an audi a4 key replacement G28 Engine Speed Sensor

Charles the Humble Technician shows how to replace the G28 Engine Speed Sensor. The sensor is situated near the edges of the transmission, above the flywheel ring gear. It sends a signal to the ECU via the grey wire (T55/49) and then to the tachometer in the instrument cluster.

1. Engine Speed Sensor

The grey wire is located on the edge of transmission, just above the flywheel ring. The sensor sends 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 inside the instrument cluster.

The sensor is used to connect the G40 Camshaft position Sensor. The ecu has to be aware of when the crankshaft has reached TDC, and the location of the camshaft in order to activate the spark and injectors.

If this sensor fails to function, the ECU will display a P00160 error code. This means that the Crank Shaft is out of line with the Intake Camshaft. It could also be a sign of an issue with the chain or a jump in the chain link of the upper timing chain. However, the error code won't appear on its own without additional information from other sensors (G4 and G40).

Testing is a bit tricky since there are two connector pins, and they perform different functions however the best method 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 are having problems with this component, look for signs of coolant or oil in the connector bay.

2. Injectors

Yesterday, while accelerating at full speed from the highway paytoll i had massive power loss as if the engine was running out of gas or injectors aren't firing anymore. I pulled out the spark plugs this morning and found that 3 were soaked with gasoline and the fourth was unclean. When I crank the engine, there are no sparks i put tissue on top of each injector hole and the 3 drenched with gazoline leap out, however the 4th stay shut. I checked the ground connection on ECU pins 14/55,30/55 and 48/55 i get zero Ohm. Therefore, i think the issue is elsewhere.

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

I'm not sure what to do, i believe that i've ruled out 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 by the RPM sensor. The GM-style transmitter 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 at a parts store. It is simple to test them to do - just put your DMM in resistance mode and take measurements 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 should be infinite Ohms.

4. ECU

Our 20vt turbo (3B AAN, ABY, and ADU) engines have an ECU that needs to be aware of the speed and position of the crankshaft to make decisions about timing of the fuel injector, for example. To accomplish this, it makes use of a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If you have a problem with either of these sensors, the diagnostic scanner will show codes that could cause the engine shutting down.

A failing G28 sensor could cause an inaccurate gearbox speed counter, a gearbox that shifts faster than normal, and/or an unfire when in gear. It is probable that your sensor is failing and needs to be replaced if you notice any of these signs. The good thing is that they are quite affordable and readily available, especially if you're looking at an Bosch sensor, like ours. Alternatively, the GM version of this unit is also a good option.

5. Tachometer

A damaged engine sensor could cause a variety of issues in your vehicle. It is a crucial part of the audi car key case's transmission as it sends information to the ECU about how fast or slow the car's crankshaft is rotating. If this sensor fails, it can cause problems for the transmission and 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 through an uncolored wire. The ECU then uses and processes this signal to regulate fuel, timig, and boost as well as transmitting it to the G5 Tachometer located in the instrument cluster. You can test for sensor failure by checking continuity from the sensor to the tachometer. Additionally, you can examine the continuity between pins T55/49 of the ECU and pin T6a/1 of the instrument cluster (trace [79]), and between pin T6a/1 and pin T26a/12. There should be an average resistance of 1000 ohms in these areas. This is a typical component across the audi key replacement near me q5 key (https://kingbookmark.com/story18263584/Ten-Things-you-learned-in-kindergarden-they-ll-help-you-understand-audi-g28) 80 100 200, UrS and RS2 range from 1985 MC until the 1997 UrS AAN and 1995 RS2 ADU so good ones might be availble in wrecking yards.