How to Replace an audi replacement key service tt audi a3 key replacement programming (Gorillainvestment post to a company blog) G28 Engine Speed Sensor

In this video Charles the Humble Mechanic shows how to replace the G28 engine speed sensor. The sensor is located on the edge 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 on 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 using the grey wire. The ECU uses this information to regulate the amount of fuel and boost. It also sends an indicator to the G5 Tachometer within the instrument cluster.

The sensor serves as a reference for comparing with the G40 Camshaft Position Sensor. The ecu must know when the crankshaft has reached TDC and also where the camshaft lies to trigger the spark and injectors.

If this sensor fails the ECU will display a P00160 code which means the Crank Shaft and Intake Camshaft aren't in sync and possibly indicating chain stretch or a jumped link on the upper chain of timing. The code won't show without the additional information provided by other sensors (G4 or G40).

Testing is a bit challenging as there are two different connector pins, and they serve different purposes but the best way to test it is by measuring resistance between the sensor and the ECU. It should read around 1000 ohms when it is at full operation. Check for signs of coolant or oil in the connector bay if you have issues with this part.

2. Injectors

Yesterday, as i was accelerating off the highway paytoll at maximum speed, i noticed a huge reduction in power. It was like the engine had run out of gas. Or my injectors weren't firing. I pulled out the spark plugs this morning, 3 were soaked with gasoline and the 4th was dry. I put a piece of tissue over each hole in the injector and when I start the engine without sparks, the 3 with gazoline jump right out. The fourth one remains closed. I checked the ground connection of ECU pins 14,30, and 48/55. I found zero ohm. I'm assuming that the issue is elsewhere.

I also tried to reset the PID without success. The car key replacement audi will start when the G28 is disconnected, but it runs fine with the G28 plugged in. However the intermittent misfire issue continues to occur at higher RPM. The temperature sensor for the coolant (G62) shows the wrong temp value -49c, even if I unplug it. Also i noticed that the gauge for oil pressure in the cockpit is showing 2 bar while the actual pressure is 0.0 when I crank up the engine.

I don't know what to do. I believe that I've all other possibilities out. I'm worried that i might have missed something. Let me know should you have any suggestions! TIA!

3. Fuel Pump

The fuel pump in the g28 can be activated by a signal sent by 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. You can easily locate an extra in a wrecking shop or a parts store. Testing them is easy to do - just put your DMM in resistance mode and take measurements 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

The ECU of our 20vt turbo (3B AAN ABY ADU) engines must know the position and speed of the crankshaft to determine timing of fuel injectors, etc. In order to do this it makes use of a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If you encounter a problem with either one of these, the diagnostic scanner will display codes that could lead to an engine shut down.

Some of the symptoms of a malfunctioning G28 sensor are an inaccurate gearbox rev counter and gears that shift faster than normal, and/or a misfire when you're in gear. It is probable that the sensor is failing and requires to be replaced if you experience any of these signs. They're inexpensive and easy to locate, especially in the case of a Bosch sensor like ours. Alternately, GM's version this part is a good option.

5. Tachometer

A malfunctioning engine sensor can cause a myriad of issues in your vehicle. It is a crucial part of the audi key fob replacement cost's transmission because it communicates to the ECU about how the car's crankshaft is rotating. This sensor can cause the transmission to malfunction and other components in the car to be affected.

The G5 engine speed sensor is located on the outside of the transmission just above the flywheel ring gear. It sends a signal to the ECU at pin T55/49 via a grey wire. The ECU then processes this signal to regulate fuel, timig and boost and then transmitting it to the G5 tachometer inside the instrument cluster. You can check the sensor for failure by checking 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 see approximately 1000 ohms of resistance between these two points. This is a standard component across the audi a3 key replacement 80 100 200, UrS and RS2 range from 1985 MC to the 1997 UrS AAN and 1995 RS2 ADU. Good ones could be available in wrecking yards.