lunchcatsup4

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. The sensor is situated at the top of the transmission, above the flywheel ring gear. It transmits a signal the ECU via the grey wire (T55/49) and then to the tachometer in the instrument cluster. 1. Engine Speed Sensor It is located on the outside of the transmission just above the flywheel ring gear G28 Engine Speed Sensor sends signals to ECU pin T55/49 through an uncolored wire. The ECU then uses this information to control the flow of fuel, timig and boost. It also sends an indication to the G5 Tachometer located in the instrument cluster. The sensor is used to link 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 when it fails, the ECU will display a P00160 error code. This indicates that the Crank Shaft is out of line with the Intake Camshaft. It could also indicate the possibility of a chain stretch or jumped chain link in the upper chain. The code won't show without the additional information provided by other sensors (G4 or G40). It's a bit tricky to test as there are different pins on the connector and they all have different functions. The best method for doing this is by measuring the resistance between the ECU and the sensor. When the sensor is fully functional, it should read about 1000 ohms. Look for signs of coolant, or oil in the connector bay if you have issues with this part. 2. Injectors Yesterday, while accelerating from the highway paytoll at full speed I noticed a massive reduction in power. It was like the engine had run out of gas. Or, my injectors were not firing. I pulled out the spark plugs this morning, 3 were drenched in gasoline and the 4th was dry. I put a piece of tissue over each hole in the injector and when i turn the engine on without sparks, the ones with gazoline jump out. The 4th one remains closed. I inspected the ground connection on ECU pins 14/55, 30/55 and 48/55. i get zero Ohm. I assume that the problem is somewhere else. I also tried to reset the PID without success. The car will start when the G28 is disconnected, but it is running fine with the G28 plugged in. However the intermittent misfire issue persists at higher RPM. The coolant sensor (G62) even when unplugged, still shows an ice temperature of -49c. I also noticed that the oil gauge in the cockpit shows 2 bar but the actual pressure is 0. I'm not sure what to do, i feel i have pretty much completely ruled out all other possibilities. I'm afraid i may have missed something. If anyone has any suggestions, please chime in! TIA! 3. Fuel Pump The fuel pump in the g28 is activated by a signal by the RPM sensor. The GM-style transmitter is similar to the G4 sender, and both operate 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 easy to test them – just switch your DMM into resistance mode and test the distance between pins 1 and 2 (with the bump at the connector end facing upwards). They should be infinite Ohms. 4. ECU The ECU in our 20vt turbo (3B AAN ABY ADU) engines requires to be aware of the speed and position of the crankshaft to make decisions regarding timing of fuel injectors, etc. It makes use of a Crank Position Sensor G4 and an Engine Speed Sensor G28 to achieve this. If audi q7 keys locked in car of these goes bad you will get codes on the diagnostic scanner that can lead to engine shutdown. Some of the signs of a failed G28 sensor include an inaccurate gearbox rev counter, gears shifting quicker than normal and/or misfiring when in gear. It is possible that the sensor is failing and needs to be replaced if you experience any of these signs. The good thing is that they are very affordable and easy to find particularly in the case of the Bosch sensor, which is what we have. If you prefer, GM's version of this part is an excellent choice. 5. Tachometer A damaged engine sensor could cause a number of problems in your vehicle. It's an essential component of the transmission in your Audi since it sends information to the ECU on how fast or slowly the engine is spinning. If the sensor fails, it can disrupt 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, just above the flywheel ring. It sends a signal via an uncolored wire to the ECU pin T55/49. The ECU uses this signal to control the amount of fuel and boost, as well as timig. It also sends 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. Also, you can examine the continuity between pins 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 approximately 1000 ohms of resistance between those two pins. This is a standard part that is found across the Audi 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.