20 Myths About Audi G28: Dispelled

How to Replace an audi key fob not working G28 Engine Speed Sensor

Charles the Humble Technician teaches you how to replace the G28 Engine Speed Sensor. This sensor is situated near the transmission's edge, above the flywheel gear. It sends a message to the ECU via the grey wire T55/49 and then to the tachometer in the instrument cluster.

1. Engine Speed Sensor

Located on the edge of the transmission just above the flywheel ring gear the G28 Engine Speed Sensor sends signals to ECU pin T55/49 via the grey wire. The ECU uses this information to control boost and fuel. It also sends an indicator to the G5 Tachometer located in the instrument cluster.

The sensor is used to link with the G40 Camshaft position Sensor. The ecu must be aware 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 display the P00160 error, which means the Crank Shaft and Intake Camshaft are out of sync, possibly indicating chain stretch or a jumped link on the upper chain of timing. However, the error code won't be displayed on its own without additional information from other sensors (G4 and G40).

It's a bit tricky to test because there are several pins on the connector, and they all have different functions. The best method for doing this is to measure the resistance between the ECU and the sensor. When the sensor is operational, it should be reading around 1000 ohms. If you're experiencing issues with this component, look for evidence of oil or coolant in the connector bay.

2. Injectors

Yesterday, while accelerating at full speed from the highway paytoll i had a big cut in power like the engine is running out of gas or the injectors are not firing anymore. Today, Audi keyless go i pulled out the spark plugs, 3 were drenched with gazoline the fourth one was dry. When I crank the engine with no sparks i put tissue on top of each injector hole and the 3 that were drenched in gazoline jump out but the 4th stay shut. I checked the ground connection on ECU pins 14/55, 30/55 and 48/55. i get 0ohm. I think the issue is elsewhere.

I also tried to reset PID but without success. The car will start when the G28 is disconnected, but it works fine when the G28 connected. However, the intermittent misfire problem still occurs at higher RPM. The temperature sensor for coolant (G62) shows the wrong temperature value of -49c even when i unplug it. I also noticed that the oil gauge in the cockpit shows 2 bar while the actual pressure is 0.

I'm not sure what to do, i believe that i've ruled out everything else. But i'm worried that I may have missed something. If anyone has any suggestions, please share them! 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 work on the 80,100,200, UrS, and RS2 vehicles. You can easily locate the audi a3 spare key in a salvage shop or a parts store. Test them out 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 end). They must be infinite ohms.

4. ECU

The ECU of our 20vt turbo (3B AAN ABY) engines needs to be aware of the speed and position of the crankshaft in order to make a decision about fuel injector timing, 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 sensors, the diagnostic scanner will show codes that could lead to an engine shutdown.

Some of the symptoms of a failed G28 sensor include an inaccurate gearbox rev counter the gears are shifting faster than normal and/or misfiring when you are in gear. It is probable that your sensor is failing and requires to be replaced if you experience any of these symptoms. The good thing is that they are quite affordable and easy to find particularly in the case of a Bosch model, which is what we have. You can also choose the GM version of this unit is also a good choice.

5. Tachometer

A failing engine speed sensor could be the cause of numerous issues in your car. It is a crucial part of your audi smart key replacement's transmission, as it sends information to the ECU about how fast or slow the vehicle's crankshaft is spinning. This sensor can cause the transmission to malfunction and other car components to be affected.

The G5 engine sensor is located at the edge of transmission, above the flywheel ring. It sends signals via gray wire to ECU pin T55/49. The ECU uses this signal to control fuel and boost, and also timig. It also transmits it to the G5 Tachometer inside the instrument cluster. You can test the sensor audi A1 keys for any failure by checking the continuity between it and the tachometer, between ECU pin T55/49 and the instrument cluster connection on pin T6a/1 (trace [79trace [79]) and between T6a/1 and the instrument cluster pin T26a/12. You should see a resistance of approximately 1000 ohms between these two points. This is the same across the Audi key copy 80-100-200-RS2 series, starting from the 1985 MC all the way up to the 1997 UrS AN and the 1995 RS2 Du So, you may find good ones in wrecking yards.