How to Replace an audi keys replacement smart audi tt key fob not working replacement (learn more about perfectworld.wiki) 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 outside of the transmission, above the flywheel gear. It transmits a signal the ECU via an uncolored wire (T55/49) and then to the tachometer in the instrument cluster.

1. Engine Speed Sensor

The sensor is located at the edge of the transmission above the flywheel ring gear the G28 Engine Speed Sensor sends a signal to ECU pin T55/49 through an uncolored wire. The ECU uses this information to control boost and fuel. 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 know when the crankshaft is TDC and where the camshaft is located so that it can trigger spark and injectors accordingly.

If this sensor fails, the ECU will display a P00160 code which means the Crank Shaft and Intake Camshaft are out of sync and could indicate chain stretch or a jumped link on the upper timing chain. However, the error 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 as there are several pins on the connector and each has its own functions. The best method for doing this is by measuring the resistance between the ECU and the sensor. When the sensor is operational, it should read around 1000 ohms. Look for signs of coolant or oil in the connector bay if there are issues with this component.

2. Injectors

Yesterday accelerating full speed from highway paytoll i had a big cut in power like the engine is out of gas or injectors aren't firing at all. This morning i pull out the spark plugs, 3 were soaked with gazoline and the fourth was dry. I placed a tissue over each injector hole, and when i turn the engine on without sparks, the three with gazoline jump right out. The fourth one remains closed. I tested the ground connection of ECU pins 14,30 and 48/55. I found 0ohm. I'm assuming the issue is somewhere else.

I also tried to reset the PID without success. The car can start when the G28 is unplugged and it runs perfectly when it is plugged in however it is experiencing intermittent misfires at higher RPM. The coolant sensor (G62) even when it is unplugged, shows an ice temperature of -49c. I also noticed that the oil gauge in the cockpit shows 2 bars but the actual pressure is 0.

I'm not sure what to do. I think I've all other possibilities out. However, i'm afraid that i might have missed something. If anyone has suggestions, please share them! TIA!

3. Fuel Pump

The fuel pump in the g28 gets a signal from the RPM sensor. The GM-style transmitter functions similarly to the G4 sender and both work on the 80,100,200, UrS, and RS2 vehicles. You can easily locate the spare in a salvage shop or a parts store. It is easy to test them: simply switch your DMM into resistance mode and test 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 in our 20vt turbo (3B AAN ABY ADU) engines requires to be aware of the position and speed the crankshaft in order to make a decision about timing of fuel injectors, etc. It utilizes a Crank Position Sensor G4 and an Engine Speed Sensor G28 to achieve this. If you encounter a problem with either of these, the diagnostic scanner will display the codes that could trigger an engine shut down.

A malfunctioning G28 sensor could cause an inaccurate gearbox speed counter or a gearbox that shifts faster than normal, or a misfire in gear. If you have any of these issues it is most likely that your sensor is failing and requires replacement. The good thing is that they are very cheap and easily accessible particularly if you're looking at a Bosch model, like ours. You can also choose the GM version of this unit is also a great option.

5. Tachometer

A damaged engine sensor could cause a myriad of issues within your vehicle. It is a crucial part of your audi tt key programming's transmission, because it communicates to the ECU about how the car's crankshaft is spinning. If the sensor fails, it could cause problems for the transmission as well as the rest of the car's components.

The G5 engine speed sensor is located at the outside of the transmission above the flywheel ring gear and transmits a signal to the ECU at pin T55/49, via an uncolored wire. The ECU then processes the signal to control the flow of fuel, timig and boost, and also sends it on to the G5 tachometer inside the instrument cluster. You can check the sensor for any failure by checking the continuity between it and the tachometer, between the ECU pin T55/49 and the instrument cluster connection via pin T6a/1 (trace [79trace [79]) as well as between T6a/1, and the instrument cluster pin T26a/12. There should be an average resistance of 1000 ohms between these two points. This is a standard part that is found across the audi keys 80, 100, 200, UrS and RS2 range from 1985 MC to the 1997 UrS AAN and 1995 RS2 ADU. Good parts could be found in wrecking yards.