Its History Of Audi G28
Its History Of Audi G28
Blog Article
How to Replace an Audi G28 Engine Speed Sensor
Charles the Humble Technician shows how to replace the G28 Engine Speed Sensor. The sensor is situated on the edge of the transmission, above the flywheel ring gear. It sends a signal to the ECU via a grey wire (T55/49) and then to the tachometer located in the instrument cluster.
1. Engine Speed Sensor
Located on the edge of the transmission, above the flywheel ring gear the G28 Engine Speed Sensor sends signals to ECU pin T55/49 via a grey wire. The ECU utilizes this information to regulate boost and fuel. It also sends signals to the G5 tachometer inside the instrument cluster.
The sensor serves as a reference point to connect with the G40 Camshaft Position Sensor. The ecu must know when the crankshaft is TDC and where the camshaft is so it can activate spark and injectors according to the situation.
If this sensor fails, the ECU will throw a P00160 code which means the Crank Shaft and Intake Camshaft aren't in sync and possibly indicating the chain is stretched or a jump link on the upper timing chain. However, the error code won't appear on its own without additional information from other sensors (G4 and G40).
It's a bit tricky to test as there are various 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. When the sensor is fully functional, it should read around 1000 ohms. If you're experiencing issues with this part, check for evidence of coolant or oil in the connector bay.
2. Injectors
Yesterday accelerating full speed from highway paytoll, I experienced an abrupt drop in power like the engine is running out of gas or injectors are not firing any more. I took out the spark plugs this morning, 3 were drenched in gasoline and the fourth was dry. I placed a tissue over each hole in the injector and when I start the engine without sparks, the ones that have gazoline pop right out. The fourth one remains closed. I tested the ground connection of ECU pins 14,30, and 48/55. I got zero ohm. I think the issue is somewhere else.
I also tried to reset the PID but without success. The car can start if the G28 is disconnected and is running fine when it is connected however it has intermittent misfire issues at higher RPM. The temperature sensor for coolant (G62) shows the wrong temperature value of -49c, even if I unplug it. Also, i noticed that the oil pressure gauge in the cockpit is showing 2 bar when the actual pressure is 0.0 when I crank up the engine.
I don't know what to do. I think I've eliminated everything else. I'm afraid i may have missed something. Please let me know If you have any suggestions! TIA!
3. Fuel Pump
The fuel pump in the g28 receives a signal from the RPM sensor. The GM-style sensor is identical to the G4 and both are used in the 80, 100 200, UrS and RS2 new audi key cars so you can easily find one at a wrecking yard or in a local parts store. It is simple to test them - simply put your DMM into resistance mode and determine the distance between pins 1 and 2 (with the bump at the connector end facing up). They should 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 fuel injector timing, etc. It makes use of a Crank Position Sensor G4 and an Engine Speed Sensor G28 to achieve this. If you are experiencing issues with either one of these, the diagnostic scanner will display codes that could cause the engine shutting down.
A malfunctioning G28 sensor could cause an inaccurate gearbox speed counter, a gearbox that shifts more quickly than normal, or a misfire in gear. If you have any of these issues, it is likely your sensor is going bad and requires replacement. The good news is they are quite affordable and easily accessible particularly when you're looking at an Bosch model, which is what ours are. If you prefer, GM's version of this part is an option.
5. Tachometer
A malfunctioning engine sensor can cause a variety of issues within your vehicle. It's an essential component of the Audi's transmission check here because it communicates to the ECU about how fast or slow the car's crankshaft is turning. This sensor can cause the transmission to fail and other components in the car to be check here affected.
The G5 engine sensor is located near the edge of the transmission, over the flywheel ring. It sends an electrical signal through gray wire to ECU pin T55/49. The ECU is then able to process this signal to regulate the flow of 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 checking continuity between it website and the tachometer. You can also check continuity between ECU pin T55/49 and the instrument cluster connection to pin T6a/1 (trace [79trace [79]) and between T6a/1 and the instrument cluster pin T26a/12. You should observe approximately 1000 ohms resistance between these two 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 1995 RS2 Du So, replace audi key you may find some good ones in wrecking yards.