Why Nobody Cares About Audi G28

How to Replace an audi car key cover A3 spare audi key fobs, itkvariat.com, 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 just above the flywheel gear. It transmits a signal to the ECU via a grey wire (T55/49), then to the tachometer within the instrument cluster.

1. Engine Speed Sensor

The sensor is located at the edge of the transmission, above the flywheel ring gear, the G28 Engine Speed Sensor sends signals to ECU pin T55/49 via a grey wire. The ECU utilizes this information to regulate fuel and boost. It also sends an alert to the G5 Tachometer within the instrument cluster.

The sensor is used to connect with the G40 Camshaft position Sensor. The ecu needs to know when the crankshaft is TDC and where the camshaft is located so that it can activate spark and injectors in the right way.

If this sensor fails the ECU will display a P00160 code which means the Crank Shaft and Intake Camshaft aren't in sync and possibly indicating the chain is stretched or a jump link on the upper timing chain. However the code will not appear on its own without additional information from other sensors (G4 and G40).

It can be a bit difficult to test because there are several pins on the connector, and they all have different functions. The most effective method to test it is to measure the resistance between the ECU and the sensor. When the sensor is operational, it should be reading approximately 1000 ohms. If you are having problems with this component, look for evidence of oil or coolant in the connector bay.

2. Injectors

Yesterday, when accelerating from highway paytoll at a high speed I noticed a massive drop in power. It was as if the engine had run out of gas. Or my injectors weren't firing. This morning i pull out the spark plugs, 3 were drenched with gazoline the fourth one was dry. I put a piece of tissue over each injector hole, and when I turn the engine on without sparks, the 3 with gazoline jump out. The fourth one remains closed. I checked the ground connection on ECU pins 14/55,30/55 and 48/55 i get zero ohm. I think the issue is in another location.

I also tried to reset the PID without success. The car can start when the G28 is not plugged in and it runs perfectly when it is plugged in but it still has the intermittent misfire issue at higher RPM. The temperature sensor for coolant (G62) shows the wrong temperature value of that is -49c even after unplugging it. Also i noticed that the oil pressure gauge in the cockpit is showing 2 bar while the actual pressure is 0.0 when i rev the engine.

I don't know what to do. I feel like i've pretty much eliminated everything else. However, i'm afraid that I might have missed something. If anyone has any ideas please let me know! TIA!

3. Fuel Pump

The fuel pump of the g28 gets a signal from the RPM sensor. The GM-style transmitter functions similarly to the G4 sender and works on the 80,100,200, UrS, and RS2 vehicles. You can easily find a spare in a wrecking shop or parts store. It is simple to test them: simply put your DMM into resistance mode and test the distance between pins 1 and 2 (with the bump at the connector's end facing up). They must be infinite ohms.

4. ECU

Our 20vt turbo (3B AAN, ABY, and ADU) engines have an ECU that must know the position and speed of the crankshaft to make decisions regarding timing of the fuel injector, for example. To accomplish this, it makes use of a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If either of these goes wrong, you will receive codes on the diagnostic scanner which can cause the engine to shut down.

A failing G28 sensor could result in an inaccurate speed counter for the gearbox and a gearbox which shifts more quickly than normal, and/or a misfire in the gear. It is likely that the sensor is failing and needs to be replaced if you notice any of these symptoms. They're cheap and easy to find especially when they're a Bosch model like ours. If you prefer, GM's version of this part is a good option.

5. Tachometer

A failing engine speed sensor could be a cause for a slew of problems in your vehicle. It's an essential component of the transmission in your audi a3 replacement key because it relays information to the ECU about how fast or slow the engine is turning. If this sensor fails, it can disrupt the performance of the transmission, as well as the rest of the car's components.

The G5 engine speed sensor is located on the edge of the transmission just above the flywheel ring gear. It sends a signal to the ECU at pin T55/49 through an uncolored wire. The ECU utilizes this signal to control the flow of fuel and boost and also to timigrate. It also transmits it to the G5 Tachometer in instrument cluster. You can test for sensor failure by examining the continuity from the sensor to the tachometer. Also, you can examine the continuity between pins T55/49 of the ECU and pin T6a/1 of the instrument cluster (trace [79trace [79]) and between pin T6a/1 as well as pin T26a/12. It should show approximately 1000 ohms resistance between these two points. This is a typical component across the audi spare keys 80 100, 200, UrS and RS2 range from 1985 MC to the 1997 UrS AAN and 1995 RS2 ADU, so the best parts could be found in wrecking yards.