How to Replace an audi key replacement cost uk G28 Engine Speed Sensor

In this video, Charles the humble mechanic demonstrates how to replace the G28 engine speed sensor. This sensor is situated at the edge of transmission over the flywheel gear. It sends a signal to the ECU via a grey wire (T55/49), then to the tachometer within the instrument cluster.

1. Engine Speed Sensor

The grey wire is located on the outside of the transmission, just above the flywheel ring. This sensor sends an electrical signal through the grey wire to pin T55/49. The ECU utilizes this information to regulate boost and fuel. It also sends a signal to the G5 Tachometer located in the instrument cluster.

The sensor is used to link with the G40 Camshaft position Sensor. The ecu needs to know when the crankshaft reached TDC, and the location of the camshaft in order to activate the spark and injectors.

If this sensor fails, the ECU will show an error code P00160 which indicates that the Crank Shaft and Intake Camshaft aren't in sync and possibly indicating chain stretch or a jumped link on the upper timing chain. However, the code won't be displayed on its own without additional information from other sensors (G4 and G40).

Testing is a bit tricky since there are two connector pins and they perform different functions but the most effective method to test it is to measure the resistance between the sensor and the ECU. When the sensor is operational, it should read about 1000 ohms. If you're experiencing issues with this part, check for evidence of oil or coolant in the connector bay.

2. Injectors

Yesterday, when accelerating from highway paytoll at full speed I noticed a significant reduction in power. It was like the engine was running out of gas. Or, my injectors weren't firing. I took out the spark plugs this morning, three were soaked in gasoline, and the fourth was dry. I placed a tissue over each hole in the injector and when I start the engine with no sparks, the three with gazoline jump out. The 4th one stays closed. I tested the ground connection of ECU pins 14,30 and 48/55. I found 0ohm. I'm assuming that the issue is in another location.

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

I'm not certain what to do, as i feel i have pretty much ruled out everything else. I'm concerned that i may have missed something. If anyone has suggestions, please share them! TIA!

3. Fuel Pump

The fuel pump in the g28 receives signals from the RPM sensor. The GM-style transmitter 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 from a parts store. Test them out by putting 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 end). They must be infinite Ohms.

4. ECU

Our 20vt turbo (3B, AAN, ABY and ADU) engines are equipped with an ECU that must know the position and speed of the crankshaft in order to make decisions regarding timing of the fuel injector, for example. In order to do this it makes use of a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If either of these go wrong, you will receive codes on the diagnostic scanner that can lead to engine shutdown.

A malfunctioning G28 sensor could result in an inaccurate speed counter for your gearbox or a gearbox that shifts faster than normal, or a misfire while in gear. It is probable that the sensor is failing and requires to be replaced if you encounter any of these signs. The good news is that they are very cheap and easily accessible, especially if you're looking at the Bosch sensor, like ours. Alternately, GM's version this part is a good option.

5. Tachometer

A failing engine speed sensor could be the cause of many issues in your vehicle. It is a crucial part of the audi car key holder's transmission because it communicates to the ECU about how fast or slow the vehicle's crankshaft is spinning. This sensor can cause the transmission to malfunction and other components of the car to be affected.

The G5 engine speed sensor is located at the edge of the transmission above the flywheel ring gear. It transmits 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 transmitting it to the G5 tachometer in the instrument cluster. You can determine if the sensor is in failure by checking continuity from the sensor to the tachometer. Also, you can check continuity between pin T55/49 of the ECU and pin T6a/1 of the instrument cluster (trace [79trace [79]) and audi Smart Key replacement between pin T6a/1 as well as pin T26a/12. You should see approximately 1000 ohms resistance between these two points. This is a standard part that is found across the Audi q7 key 80, 100 200, UrS and RS2 range from 1985 MC to the 1997 UrS AAN and 1995 RS2 ADU, so the best ones could be available in wrecking yards.