How to Replace an Audi G28 Engine Speed Sensor
Charles the Humble Technician teaches you 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 an uncolored wire T55/49, then to the tachometer in the instrument cluster.
1. Engine Speed Sensor
The grey wire is situated on the outside of the transmission, just 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 located in the instrument cluster.
The sensor is used to connect with the G40 Camshaft position Sensor. The ecu must be aware of when the crankshaft has reached TDC and also where the camshaft lies so that it can activate the spark and injectors.
If this sensor fails to function, the ECU will display an error code P00160. This means that the Crank Shaft is out of line with the Intake Camshaft. It could also be a sign of an issue with the chain or a jump in the chain link of the upper chain. The code won't show without the additional information provided by other sensors (G4 or G40).
It can be a bit difficult to test as there are various pins on the connector and they all have different functions. The best way to do it is to measure the resistance between the ECU and the sensor. It should read about 1000 ohms when it is operating at its maximum. Look for evidence of coolant or oil in the connector bay if you have issues with this component.
2. Injectors
Yesterday, while accelerating at full speed from the highway paytoll i had massive power loss as if the engine was running out of gas or injectors aren't firing any more. I pulled out the spark plugs this morning and found that 3 were soaked in gasoline, and the fourth was unclean. When I crank the engine without sparks, i place a tissue on top of each injector hole and the 3 that were drenched in gazoline leap out, however the 4th one stays shut. I tested the ground connection on ECU pins 14/55/30/55/48/55/14/55/48/ I get zero Ohm. I'm assuming the issue is in another place.
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 persists at higher RPM. The temperature sensor for the coolant (G62) shows the wrong temperature of -49c even when i unplug it. I also noticed that the oil gauge in the cockpit shows 2 bars when the actual pressure is 0.
I'm not sure what to do. I believe that I've all other possibilities out. But i'm worried that I may have missed something. Please let me know if you have any ideas! TIA!
3. Fuel Pump
The fuel pump in the g28 gets a signal from the RPM sensor. The GM-style sender is the same as the G4 and both function in the 80 100 200, UrS and RS2 cars which is why you can easily locate one at a junkyard or in a local parts store. Testing check here them is easy - put your DMM in resistance mode and measure between pins 1 (with the bump on the connector's side up) and 2 (2nd from left on the black connector's side). They must be infinite Ohms.
4. ECU
The ECU in our 20vt turbo (3B AAN ABY) engines must know both the here position and speed the crankshaft to determine timing of the fuel injector, etc. It utilizes a Crank Position Sensor G4 and an Engine Speed Sensor G28 to achieve this. If either of these goes badly, you will see codes on the diagnostic scanner which could cause engine shut down.
Some of the symptoms of a malfunctioning G28 sensor are an inaccurate rev counter in the gearbox the gears are shifting faster audi spare key than normal and/or misfiring when you are in gear. It is possible that the sensor is failing and needs to be replaced if you notice any of these signs. They are cheap and check here easy-to-find particularly in the case of an Bosch unit like ours. If you prefer, GM's version of this part is an excellent choice.
5. Tachometer
A failing engine sensor could cause a variety of issues within your vehicle. It's get more info an essential component of the transmission of your Audi since it sends information to the ECU regarding how fast or slow the car's engine is spinning. This sensor can cause the transmission to malfunction and other components of the car to be affected.
The G5 engine sensor is located at the outskirts of the transmission, just above the flywheel ring. It transmits an electrical signal through an uncolored wire to the ECU pin T55/49. The ECU utilizes this signal to regulate the amount of fuel and boost, and also to timigrate. It also sends it to the G5 Tachometer in instrument cluster. You can test the sensor for any failure by checking the continuity between it and the tachometer. You can also check continuity between ECU pin T55/49 and the instrument cluster connection to pin T6a/1 (trace [79]) and between T6a/1 and the instrument cluster pin T26a/12. You should detect an average resistance of 1000 ohms between these points. This is the same across the Audi 80-100-200-RS2 series, starting from the 1985 MC up to the 1997 UrS AN and the 1995 RS2 DU So, you may find them in wrecking yards.