How to Replace an audi key replacement G28 Engine Speed Sensor

Charles the Humble Technician shows you how to replace the G28 Engine Speed Sensor. The sensor is located on the outside of the transmission over the flywheel gear. It transmits a signal to the ECU via an uncolored wire T55/49, then to the tachometer on the instrument cluster.

1. Engine Speed Sensor

It is located on the outside of the transmission, above the flywheel ring gear G28 Engine Speed Sensor sends signals to ECU pin T55/49 through a grey wire. The ECU utilizes this information to regulate the amount of fuel and boost. It also sends a signal to the G5 tachometer 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 trigger spark and injectors accordingly.

If this sensor fails, the ECU will show a P00160 code which means the Crank Shaft and Intake Camshaft aren't in sync and could indicate chain stretch or a jumped link on the upper timing chain. However, the code won't appear on its own without additional information from other sensors (G4 and G40).

It is a little tricky to test because there are different pins on the connector and they all have different functions. The most effective method to test it is by measuring the resistance between the ECU and the sensor. It should read around 1000 ohms if the sensor is at full operation. If you're experiencing issues with this part, check for signs of oil or coolant in the connector bay.

2. Injectors

Yesterday, when accelerating from highway paytoll at full speed I noticed a massive drop in power. It was like the engine had run out of gas. Or, my injectors were not firing. This morning i pull out the spark plugs, 3 were drenched with gazoline the fourth one was dry. I placed a tissue over each hole in the injector and when I start the engine without sparks, the 3 with gazoline jump out. The fourth one remains shut. I inspected the ground connection on ECU pins 14/55, 30/55 and 48/55. I get 0ohm. I think the issue is somewhere else.

I also tried to reset the PID without success. The car is able to start if the G28 is unplugged and it runs perfectly when it is connected but it still is experiencing intermittent misfires at higher RPM. The coolant sensor (G62) even when unplugged, still shows a temperature of -49c. I also noticed that the oil gauge in the cockpit shows 2 bar while the actual pressure is zero.

I don't know what to do. I feel like i've pretty much eliminated everything else. I'm concerned that i may have missed something. If anyone has any ideas please chime in! TIA!

3. Fuel Pump

The fuel pump in the g28 can be activated by a signal sent by the RPM sensor. The GM-style sender is identical to the G4 and both are used in the 80 100, 200, UrS and RS2 cars which is why you can easily locate one at a salvage yard or at a parts store. Test them out - put 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 have an ECU that has to know the position and audi tt key Case speed of the crankshaft in order to make decisions regarding timing of the fuel injector, for example. It utilizes a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If you encounter a problem with either of these sensors, the diagnostic scanner will display codes that could lead to the engine shutting down.

Some of the symptoms of a failing G28 sensor are an inaccurate gearbox rev counter, gears shifting quicker than normal and/or misfiring when you're in gear. It is likely that your sensor is failing and requires to be replaced if you encounter any of these signs. They are cheap and easy-to-find, especially in the case of an Bosch unit like ours. If you prefer, GM's version of this component is a good option.

5. Tachometer

A malfunctioning engine sensor can cause a number of problems in your audi car keys replacement. It's a vital component of your audi car keys replacement's transmission, because it communicates to the ECU about how fast or slow the vehicle's crankshaft is turning. This sensor could cause the transmission to fail and other components in the car to be affected.

The G5 engine sensor is located at the outskirts of the transmission, just above the flywheel ring. It sends a signal via gray wire to ECU pin T55/49. The ECU utilizes this signal to control fuel and boost, as well as timig. It also relays it to the G5 Tachometer in instrument cluster. You can check the sensor for failure by examining the continuity between it and the tachometer, between ECU pin T55/49 and the instrument cluster connection via pin T6a/1 (trace [79]) as well as between T6a/1, and the instrument cluster pin T26a/12. You should observe around 1000 ohms of resistance between these two points. This is a common component across the Replacement Audi Key Cost Uk 80 100 200, UrS and RS2 range from 1985 MC through the 1997 UrS AAN and 1995 RS2 ADU. Good ones could be available in wrecking yards.