keyneck2

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 located on the outside of the transmission, above the flywheel gear. It sends a message 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 transmits signals through the grey wire to pin T55/49. The ECU uses this information to control the amount of fuel and boost. It also sends an indication to the G5 Tachometer in instrument cluster. The sensor is used to connect the G40 Camshaft position Sensor. The ecu has to know when the crankshaft reached TDC and also where the camshaft lies in order to activate the spark and injectors. If this sensor fails when it fails, the ECU will display a P00160 error code. This means that the Crank Shaft is out of sync with the Intake Camshaft. It could also be a sign of an issue with the chain or a jumpy 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 since there are several pins on the connector, and each has its own functions. The best way to do it is to measure the resistance between the ECU and the sensor. If the sensor is operational, it should be reading around 1000 ohms. If you are having problems with this sensor, look for evidence of coolant or oil in the connector bay. 2. Injectors Yesterday, while accelerating at full speed from the highway paytoll, i experienced a big cut in power like the engine is running out of gas or injectors are not firing anymore. I pulled out the spark plugs this morning, three were soaked with gasoline and the 4th was dry. I put tissue over each injector hole, and when I start the engine with no sparks, the 3 that have gazoline pop right out. The fourth one remains shut. I tried to test the ground connections of ECU pins 14,30, and 48/55. I found 0ohm. I assume that the problem is elsewhere. I also tried to reset the PID but with no luck. The car will start when the G28 is unplugged, and it is running fine with the G28 connected. However, the intermittent misfire problem persists at higher RPM. The coolant temperature sensor (G62) shows the wrong temperature of -49c even when i unplug it. Also i noticed that the oil pressure gauge in the cockpit shows 2 bar, whereas the actual pressure is 0.0 when I crank up the engine. I'm not sure what to do. I think I've ruled everything else out. audi a3 replacement key 'm afraid i may have missed something. Please let me know if you have any ideas! TIA! 3. Fuel Pump The fuel pump in the g28 is activated by a signal by the RPM sensor. The GM-style sender is identical to the G4 and they both work 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 to do – just put your DMM in resistance mode and measure the resistance between pins 1 (with the bump on the connector end up) and 2 (2nd from the left on the black end of the connector). They must be infinite Ohms. 4. ECU The ECU of our 20vt turbo (3B AAN ABY) engines must know both the position and speed the crankshaft to make decisions regarding timing of the fuel injector, etc. It makes use of a Crank Position Sensor G4 and an Engine Speed Sensor G28 to achieve this. If either of these sensors go wrong, you will receive codes on the diagnostic scanner which could cause engine shut down. Some of the signs of a failed G28 sensor are an inaccurate gearbox rev counter, gears shifting quicker than normal and/or misfiring when you are in gear. If you are experiencing any of these issues it is likely that your sensor is failing and requires replacement. They're inexpensive and easy to locate, especially when they're a Bosch unit like ours. If you prefer, GM's version of this component is an option. 5. Tachometer A malfunctioning engine sensor can cause a myriad of issues in your car. It is a crucial part of your Audi's transmission, since it relays information to the ECU about how fast or slow the vehicle's crankshaft is spinning. 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, just above the flywheel ring. It sends signals via gray wire to ECU pin T55/49. The ECU utilizes this signal to control fuel and boost, and also to timigrate. It also sends 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 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. You should observe approximately 1000 ohms of resistance between those two pins. This part is common across the Audi 80-100-200-RS2 model, ranging from the 1985 MC all the way up to the 1997 UrS AN and 1995 RS2 Du You may also find some good ones in wrecking yards.