cracklion6

How to Replace an Audi G28 Engine Speed Sensor Charles the Humble Technician teaches how to replace the G28 Engine Speed Sensor. This sensor is situated near the transmission's edge over the flywheel gear. It transmits a signal the ECU via a grey wire (T55/49), then to the tachometer located in the instrument cluster. 1. Engine Speed Sensor Located on the edge of the transmission just above the flywheel ring gear G28 Engine Speed Sensor sends signals to ECU pin T55/49 via an uncolored wire. audi key replacement utilizes this information to regulate fuel, timig and boost. It also sends an indicator to the G5 Tachometer in instrument cluster. The sensor is used as a reference point to connect with the G40 Camshaft Position Sensor. The ecu has to be aware of when the crankshaft has reached TDC, and the location of the camshaft to trigger the spark and injectors. If this sensor fails, the ECU will throw an error code P00160 which indicates that the Crank Shaft and Intake Camshaft are not in sync and possibly indicating chain stretch or a jumped link on the upper timing chain. The code won't show without the additional information provided by other sensors (G4 or G40). It is a little tricky to test since there are several pins on the connector, and each one has different functions. The best method for doing this is by measuring the resistance between the ECU and the sensor. It should read approximately 1000 ohms if the sensor is operating at its maximum. Look for signs of coolant or oil in the connector bay if there are problems with this part. 2. Injectors Yesterday, when accelerating from highway paytoll at a high speed, i noticed a huge drop in power. It was like the engine was running out of gas. Or, my injectors were not firing. In the morning, i removed the spark plugs, three were drenched with 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 and the 3 that were drenched in gazoline leap out, however the 4th stay shut. I tried to test the ground connections of ECU pins 14,30, and 48/55. I got 0ohm. So i assume the problem is in another place. I also tried to reset the PID but without success. The car is able to start if the G28 is unplugged and runs fine when it is connected but it still has the intermittent misfire issue at higher RPM. The coolant sensor (G62) even when unplugged, still shows a temperature of -49c. Also, i noticed that the oil pressure gauge in the cockpit shows 2 bar when the actual pressure is 0.0 if i crank up the engine. I'm not sure what to do, but i feel i have pretty much ruled out everything else. But i'm worried that I may have missed something. Let me know if you have any ideas! TIA! 3. Fuel Pump The fuel pump in the g28 can be activated by a signal sent from the RPM sensor. The GM-style transmitter is identical 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 – simply 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 must 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 regarding timing of the fuel injectors, etc. It utilizes a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If either of these sensors go badly, you will see codes on the diagnostic scanner that can lead to engine shutdown. Some of the signs of a malfunctioning G28 sensor are an inaccurate rev counter in the gearbox, gears shifting quicker than normal, and/or a misfire when you're in gear. If you have any of these issues it is likely your sensor is going bad and needs replacing. They are cheap and easy-to-find especially when they're an Bosch model like ours. You can also choose the GM version of this part is also a great option. 5. Tachometer A malfunctioning engine speed sensor could be the cause of a slew of issues in your car. It's an essential component of your Audi's transmission, as it sends information to the ECU about how fast or slow the vehicle's crankshaft is spinning. This sensor can cause the transmission to malfunction and other car components to be affected. The G5 engine speed sensor is located at the outside of the transmission above the flywheel ring gear and transmits a signal to the ECU at pin T55/49 via an uncolored wire. The ECU uses this signal to control the amount of fuel and boost, and also timig. It also relays it to the G5 Tachometer in instrument cluster. You can check the sensor for failure by checking continuity between it and the tachometer, between ECU pin T55/49 and the instrument cluster connection on pin T6a/1 (trace [79trace [79]) and between T6a/1 and the instrument cluster pin T26a/12. You should observe around 1000 ohms of resistance between these two points. This is a standard component across the Audi 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.