How to Replace an replacement key audi G28 Engine Speed Sensor

Charles the Humble Technician shows you how to replace the G28 Engine Speed Sensor. This 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 located on 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 a grey wire. The ECU then uses this information to control the boost, fuel, and timig. It also sends signals to the G5 tachometer inside the instrument cluster.

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

If this sensor fails, the ECU will throw an error code P00160 which indicates that the Crank Shaft and Intake Camshaft are not in sync, possibly indicating chain stretch or a jumped link on the upper timing chain. The code will not appear without the additional information provided by other sensors (G4 or G40).

It can be a bit difficult to test since there are several pins on the connector, and each has its own functions. The best method for audi replacement key fob (Mybookmark.stream) doing this is by measuring the resistance between the ECU and the sensor. It should read approximately 1000 ohms when the sensor is in full operation. If you're having issues with this part, check for evidence of coolant or oil in the connector bay.

2. Injectors

Yesterday, when i was accelerating to the fullest speed from highway paytoll, i experienced an abrupt drop in power as if the engine was running out of gas or injectors aren't firing any more. Today, i pulled out the spark plugs. Three were drenched with gazoline the fourth one was dry. I put a piece of tissue over each injector hole, and when i start the engine without sparks, the three with gazoline jump right out. The 4th one remains closed. I tried to test the ground connections of ECU pins 14,30, and 48/55. I got zero ohm. So i assume the problem is somewhere else.

I also tried to reset the PID with no success. The car will start when the G28 is disconnected, but it works fine when the G28 connected. However the intermittent misfire issue persists at higher RPM. The temperature sensor for the coolant (G62) shows the wrong temp value -49c even when i unplug it. I also noticed that the gauge for oil pressure in the cockpit shows 2 bar while the actual pressure is 0.0 when i rev the engine.

I don't know what to do. I think I've eliminated everything else. I'm afraid i may have missed something. Let me know should you have any suggestions! TIA!

3. Fuel Pump

The fuel pump of the g28 receives a signal from the RPM sensor. The GM-style sender is the same as the G4 and both function in the 80, 100 200, UrS and RS2 cars which is why you can easily locate one at a junkyard or at a parts store. It is simple to test them - put your DMM in resistance mode and measure between pins 1 (with the bump on the connector's side up) and 2 (2nd from left on the black connector's side). They must be infinite Ohms.

4. ECU

The ECU in our 20vt turbo (3B AAN ABY ADU) engines must know both the position and speed of the crankshaft in order to make a decision about timing of the fuel injector, etc. It makes use of a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If either of these sensors go bad you will get codes on the diagnostic scanner that could cause engine shut down.

The signs of a malfunctioning G28 sensor include an inaccurate rev counter in the gearbox the gears are shifting faster than normal and/or a misfire when you're in gear. If you are experiencing any of these problems, it is likely that your sensor is failing and needs replacing. The good news is they are very cheap and easy to find, especially in the case of an Bosch unit which is what we have. You can also choose the GM version of this component is also a good option.

5. Tachometer

A failing engine speed sensor could be a cause for numerous issues in your vehicle. It's a vital component of the audi tt key fob's transmission since it relays information to the ECU about how fast or slow the vehicle's crankshaft is spinning. When this sensor fails, it will affect the performance of the transmission, as well as the rest of the car's components.

The G5 engine speed sensor is located at the edge of the transmission, above the flywheel ring gear and sends a signal to the ECU at pin T55/49 via a grey wire. The ECU then processes this signal to control fuel, timig, and boost and then sends it on 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 via pin T6a/1 (trace [79]) and between pin 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 common part across the replacement audi car key 80 100 200, UrS and RS2 range from 1985 MC until the 1997 UrS AAN and 1995 RS2 ADU, so the best ones might be availble in wrecking yards.