How to Replace an audi smart key replacement G28 Engine Speed Sensor

Charles the Humble Technician teaches you how to replace the G28 Engine Speed Sensor. The sensor is located near the edges of the transmission, above the flywheel ring gear. It sends a message to the ECU through the grey wire T55/49 and then to the tachometer on the instrument cluster.

1. Engine Speed Sensor

The grey wire is situated at the edges of the transmission, just above the flywheel ring. The sensor sends an electrical signal through the grey wire to pin T55/49. The ECU then uses this information to control the boost, fuel, and timig. It also sends a signal to the G5 Tachometer located in the instrument cluster.

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

If this sensor fails, the ECU will display a P00160 code which means the Crank Shaft and Intake Camshaft are not 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).

It's a bit tricky to test because there are several pins on the connector, and they all have different functions. The best method replacement key for audi doing this is to measure the resistance between the ECU and the sensor. It should read approximately 1000 ohms when it is in full operation. If you are having problems with this component, look for signs of oil or coolant in the connector bay.

2. Injectors

Yesterday, while accelerating from the highway paytoll at full speed I noticed a significant decrease in power. It was like the engine was running out of gas. Or my injectors weren't firing. In the morning, i removed the spark plugs. Three were drenched in gazoline, the fourth was dry. I placed a tissue over each injector hole, and when i turn the engine on without sparks, the three that have gazoline pop right out. The fourth one remains closed. I tested the ground connection on ECU pins 14/55,30/55 and 48/55 I get 0ohm. So i assume the problem is somewhere else.

I also tried to reset the PID but without success. The car will start if the G28 is unplugged and is running fine when it is plugged in but it still is experiencing intermittent misfires at higher RPM. The coolant sensor (G62) even when unplugged, still shows temperatures of -49c. I also noticed that the oil gauge in the cockpit shows 2 bars when the actual pressure is zero.

I'm not sure what to do. I feel like i've pretty much ruled everything else out. I'm worried that i might have missed something. Please let me know If you have any suggestions! TIA!

3. Fuel Pump

The fuel pump on the g28 is activated by a signal by the RPM sensor. The GM-style transmitter is identical to the G4 sender and both work on the 80,100,200, UrS, jonbian.co and RS2 vehicles. You can easily locate the spare in a salvage shop or parts store. It is simple to test them: simply switch your DMM into resistance mode and Audi replacement keys test the distance between pins 1 and 2 (with the bump at the connector Audi Tt key fob end facing upwards). 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 speed and position of the crankshaft to make a decision about timing of the fuel injectors, etc. To do this, it utilizes a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If either of these goes bad you will get codes on the diagnostic scanner which could cause engine shut down.

A failing G28 sensor could result in an inaccurate speed counter for your gearbox, a gearbox that shifts more quickly than normal, or an unfire when in gear. It is probable that your sensor is failing and needs to be replaced if you experience any of these symptoms. They're inexpensive and easy to locate especially in the case of a Bosch unit like ours. Alternatively, GM's version of this part is an excellent choice.

5. Tachometer

A failing engine sensor could cause a number of problems in your vehicle. It's an essential component of your replacement key audi's transmission, because it communicates to the ECU about how the car's crankshaft is rotating. This sensor could cause the transmission to malfunction and other components in the car to be affected.

The G5 engine speed sensor is located on the edge of the transmission above the flywheel ring gear. It sends a signal directly to the ECU at pin T55/49, via a grey wire. The ECU utilizes this signal to regulate the amount of fuel and boost, and audi car key case also to timigrate. It also transmits it to the G5 Tachometer inside the instrument cluster. You can test the sensor for any failure by checking the continuity between it and the tachometer. You can also check continuity between ECU pin T55/49 and the instrument cluster connection on pin T6a/1 (trace [79]) and between T6a/1 and the instrument cluster pin T26a/12. You should detect a resistance of approximately 1000 ohms in these areas. This is a common feature across the audi key fob replacement 80-100-200-RS2 range, beginning with the 1985 MC and up to the 1997 UrS AN and 1995 RS2 Du So, you may find good ones in wrecking yards.