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. This sensor is situated near the transmission's edge, above the flywheel gear. It sends a signal to the ECU via an uncolored wire (T55/49) which is then sent to the tachometer within the instrument cluster. 1. Engine Speed Sensor The grey wire is located on the outside of the transmission, above the flywheel ring. The sensor transmits signals through the grey wire to pin T55/49. The ECU utilizes this information to control the amount of fuel and boost. It also sends an alert to the G5 Tachometer within the instrument cluster. The sensor is used to link the G40 Camshaft position Sensor. The ecu must know when the crankshaft reached TDC and also the location of the camshaft in order to activate the spark and injectors. If https://click4r.com/posts/g/17983844/30-inspirational-quotes-on-audi-spare-key fails when it fails, the ECU will display a P00160 error code. This indicates that the Crank Shaft is out of alignment with the Intake Camshaft. It could also indicate the possibility of a chain stretch or jumped chain link in the upper timing chain. However, the code won't appear on its own, without additional information from other sensors (G4 and G40). Testing is a bit challenging because there are two connector pins and they perform different functions but the best method to test it is to measure the resistance between the sensor and the ECU. When the sensor is operational, it should be reading about 1000 ohms. If you're experiencing issues with this sensor, look for signs of coolant or oil in the connector bay. 2. Injectors Yesterday accelerating full speed from highway paytoll i had massive power loss like the engine is out of gas or injectors aren't firing any more. I pulled out the spark plugs this morning, three were soaked with gasoline and the 4th was dry. When I start the engine without sparks i put tissue on the top of each of the injector holes and the 3 drenched with gazoline jump out but the 4th stays closed. I tested the ground connection of ECU pins 14,30, and 48/55. I got zero ohm. I assume that the problem is elsewhere. I also tried to reset 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 problem continues to occur at higher RPM. The coolant sensor (G62), even if it is not plugged in, shows a temperature of -49c. I also noticed that the gauge for oil pressure in the cockpit is showing 2 bar, whereas the actual pressure is 0.0 when I crank up the engine. I'm not sure what to do, i believe that i've eliminated everything else. I'm concerned that i may have missed something. Please let me know If you have any suggestions! TIA! 3. Fuel Pump The fuel pump of the g28 receives a signal from the RPM sensor. The GM-style sensor is identical to the G4 and both function in the 80, 100, 200, UrS and RS2 cars which is why you can easily locate one at a wrecking yard or at a parts store. It is simple to test them - simply switch your DMM into resistance mode and measure the distance between pins 1 and 2 (with the bump at the connector end facing up). They must be infinite Ohms. 4. ECU The ECU of our 20vt turbo (3B AAN ABY) engines requires to know the speed and position of the crankshaft in order to make a decision about timing of fuel injectors, etc. To accomplish this, it utilizes a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If you have a problem with either of these, the diagnostic scanner will show codes that could cause an engine shutdown. A damaged G28 sensor can cause an inaccurate speed counter for your gearbox or a gearbox that shifts faster than normal, or a misfire in the gear. If you have any of these issues it is most likely that your sensor is going bad and needs replacing. They are cheap and easy-to-find particularly if they're a Bosch model like ours. If you prefer, GM's version of this part would be an excellent choice. 5. Tachometer A faulty engine speed sensor could be a cause for a slew of issues with 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 rotating. If the sensor fails, it will cause problems for the transmission as well as the rest of the car's components. The G5 engine speed sensor is situated on the outside of the transmission just above the flywheel ring gear and transmits a signal 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 and then sends it on to the G5 tachometer in the instrument cluster. You can test the sensor for failure by examining the continuity between it and the tachometer, between ECU pin T55/49 and the instrument cluster connection via pin T6a/1 (trace [79]) as well as between T6a/1, and the instrument cluster pin T26a/12. You should see approximately 1000 ohms of resistance between those points. 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 good ones in wrecking yards.