pigeonmary6

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 sends a message 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, directly above the flywheel ring. The sensor sends signals through the grey wire to pin T55/49. The ECU then utilizes this information to regulate fuel, timig and boost. It also sends an indication to the G5 Tachometer in instrument cluster. The sensor is used to link with the G40 Camshaft position Sensor. The ecu must be aware of when the crankshaft has reached TDC and also the position of the camshaft, to trigger the spark and injectors. If this sensor fails, the ECU will display an error code P00160. This means that the Crank Shaft is not in line with the Intake Camshaft. It could also be a sign of a chain stretch or a jumped chain link in the upper timing chain. However the code will not appear on its own, without additional information from other sensors (G4 and G40). Testing is a bit challenging as there are two different connector pins and they have different functions however the best method of testing it is to measure resistance between the sensor and the ECU. If the sensor is functional, it should read approximately 1000 ohms. If you're experiencing issues with this part, check for signs of oil or coolant in the connector bay. 2. Injectors Yesterday, when i was accelerating to the fullest speed from highway paytoll i had massive power loss as if the engine was running out of gas or the injectors aren't firing anymore. This morning i pull out the spark plugs. Three were drenched in gazoline, the fourth was dry. When I start the engine with no sparks, I put a piece of tissue on the top of each hole in the injector and the 3 drenched with gazoline jump out but the 4th one stays closed. I checked the ground connection on ECU pins 14/55, 30/55 and 48/55. I get 0ohm. I'm assuming that the issue is elsewhere. I also tried to reset the PID without success. The car will start when the G28 is disconnected, but it runs fine with the G28 plugged in. However, the intermittent misfire problem continues to occur at higher RPM. The temperature sensor for the coolant (G62) shows the wrong temperature value of -49c even when i unplug it. I also noticed that the oil gauge in the cockpit shows 2 bar when the actual pressure is 0. I don't know what to do. I feel like i've pretty much ruled everything else out. However, i'm afraid that I might have missed something. If anyone has suggestions, please chime in! 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 identical to the G4 sender, and both operate on the 80,100,200, UrS, and RS2 vehicles. Highly recommended Internet page can easily find an extra in a wrecking shop or a parts store. Testing them is easy 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 the left on the black connector's side). They must be infinite Ohms. 4. ECU The ECU of our 20vt turbo (3B AAN ABY) engines requires to know both the position and speed of the crankshaft to make decisions regarding timing of the fuel injector, etc. To do this, it uses 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 the codes that could trigger an engine shut down. Some of the symptoms of a failing 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 are experiencing any of these issues it is likely that your sensor is deteriorating and needs replacing. They're inexpensive and easy to locate especially when they're an Bosch model like ours. If you prefer, GM's version of this part is a good option. 5. Tachometer A failing engine speed sensor could be the cause of many issues in your vehicle. It is an important part of the transmission of your Audi because it relays information to the ECU regarding how fast or slow the engine of the car is spinning. This sensor could cause the transmission to fail and other components in the car to be affected. The G5 engine sensor is located at the edge of the transmission, just above the flywheel ring. It transmits a signal via a gray wire to the ECU pin T55/49. The ECU uses this signal to control fuel and boost, and also to timigrate. It also transmits it to the G5 Tachometer in instrument cluster. You can test for sensor failure by checking continuity from the sensor to the tachometer. You can also 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 detect an average resistance of 1000 ohms in these areas. This is a typical part across the Audi 80 100 200, UrS and RS2 range from 1985 MC through the 1997 UrS AAN and 1995 RS2 ADU, so the best parts could be found in wrecking yards.