How to Replace an Audi G28 Engine Speed Sensor
Charles the Humble Technician shows you how to replace the G28 Engine Speed Sensor. The sensor is located on the outside of the transmission over the flywheel gear. It transmits a signal to the ECU through the grey wire T55/49 and then to the tachometer in the instrument cluster.
1. Engine Speed Sensor
The grey wire is located at the edges of the transmission, above the flywheel ring. The sensor sends signals through the grey wire to pin T55/49. The ECU then utilizes this information to regulate the boost, fuel, and timig. It also sends an indication to the G5 Tachometer located in the instrument cluster.
The sensor serves as a reference point to connect with the G40 Camshaft Position Sensor. The ecu must be aware when the crankshaft is TDC and the location of the camshaft so it can trigger spark and injectors accordingly.
If this sensor fails to function, 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 jump in the chain link of the upper chain. However, the code won't be displayed on its own without additional information from other sensors (G4 and G40).
It can be a bit difficult to test since there are different connector pins, and they all have different functions. The most effective method to test it is to measure the resistance between the ECU and the sensor. When the sensor is fully operational, it should be reading around 1000 ohms. If you're having issues with this sensor, look for signs of oil or coolant in the connector bay.
2. Injectors
Yesterday, as i was accelerating off the highway paytoll at maximum speed, i noticed a huge drop in power. It was like the engine had run out of gas. Or my injectors were not firing. In the morning, i removed the spark plugs. Three were soaked with gazoline and the 4th one was dry. When i crank the engine with no sparks i put tissue on the top of each of the injector holes and the 3 drenched with gazoline leap out, however the 4th stay shut. I tested the ground connection on ECU pins 14/55, 30/55 and 48/55. I get zero ohm. Therefore, i think the issue is in another place.
I also tried to reset the PID but with no luck. The car will start when the G28 is not plugged in and it runs perfectly when it is plugged in but it still is experiencing intermittent misfires at higher RPM. The coolant sensor (G62), even when it is unplugged, shows temperatures of -49c. Also i noticed that the gauge for oil pressure in the cockpit is showing 2 bar when the actual pressure is 0.0 when I crank up the engine.
I'm not sure what to do. I think I've all other possibilities out. I'm concerned that i may have missed something. Please let me know should you have any suggestions! TIA!
3. Fuel Pump
The fuel pump of the g28 gets a signal from the RPM sensor. The GM-style transmitter is similar to the G4 sender, and both operate on the 80,100,200, UrS, and RS2 vehicles. It is easy to find the spare in a salvage shop or parts store. Test them out - put your DMM in resistance mode and measure the resistance between pins 1 (with the bump on the connector's side up) and 2 (2nd from the left on the black connector's side). They must be infinite Ohms.
4. ECU
Our 20vt turbo (3B AAN, ABY and website ADU) engines have an ECU that needs to be aware of the speed and position of the crankshaft to make decisions about timing of the fuel injectors, etc. To do this, it makes use of a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If either of these go badly, you will see codes on the diagnostic scanner which can cause the engine to shut down.
A damaged G28 sensor could result in an inaccurate speed counter for your gearbox and a gearbox which shifts more quickly than normal, or an unfire when in the gear. It is possible that your sensor is failing get more info and needs website to be replaced if you experience any of these signs. They are cheap and easy-to-find especially when they're an Bosch model like ours. You can also choose the GM version of this unit is also a great option.
5. Tachometer
A malfunctioning engine sensor can cause a variety of issues in your vehicle. It's an essential component of the transmission in your Audi because it relays information to the ECU about how fast or more info slow the engine of the car is turning. When this sensor fails, it can disrupt the performance of the transmission, as well as the rest of the car's components.
The G5 engine sensor is located near the read more edge of the transmission, just above the flywheel ring. It transmits a signal via an uncolored wire to the ECU pin T55/49. The ECU then uses and processes this signal to regulate fuel, timig and boost as well as transmitting it to the G5 Tachometer located in the instrument cluster. You can check the sensor for failure by checking continuity between it and the tachometer, between ECU pin T55/49 and the instrument cluster connection to 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 these two points. This is a common feature across the Audi 80-100-200-RS2 model, ranging from the 1985 MC up to the 1997 UrS AN and the 1995 RS2 DU You may also find them in wrecking yards.