Why Nobody Cares About Audi G28

How to Replace an new audi key G28 Engine Speed Sensor

Charles the Humble Technician shows how to replace audi key the G28 Engine Speed Sensor. This sensor is situated at the edge of transmission just above the flywheel gear. It transmits a signal to the ECU via an uncolored wire (T55/49), then to the tachometer within the instrument cluster.

1. Engine Speed Sensor

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

The sensor serves as a reference for comparing with the G40 Camshaft Position Sensor. The ecu needs to know when the crankshaft reached TDC and also the position of the camshaft, so that it can activate the spark and injectors.

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

It is a little tricky to test since there are several connector pins, and they all have different functions. The best way to do it is to measure the resistance between the ECU and the sensor. If the sensor is operational, it should read approximately 1000 ohms. Examine for evidence of coolant or oil in the connector bay if you have issues with this component.

2. Injectors

Yesterday, when i was accelerating to the fullest speed from highway paytoll i had a big cut in power like the engine is out of gas or injectors aren't firing anymore. I took out the spark plugs this morning, 3 were soaked in gasoline, and the fourth was dry. When i crank the engine, there are no sparks i put tissue on the top of each hole in the injector and the 3 drenched with gazoline jump out but the 4th stay shut. I inspected the ground connection on ECU pins 14/55/30/55/48/55/14/55/48/ I get zero Ohm. I think the issue is elsewhere.

I also tried to reset the PID with no success. The car will start when the G28 is unplugged and it runs perfectly when it is connected 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. Also, i noticed that the gauge for oil pressure in the cockpit is showing 2 bar when the actual pressure is 0.0 when i rev the engine.

I'm not certain what to do, i feel i have pretty much eliminated everything else. I'm afraid i may have missed something. If anyone has any ideas 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 so you can easily find one at a wrecking yard or from a parts store. It is simple to test them: simply switch 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 are equipped with an ECU that has to know the speed and position of the crankshaft to make decisions about timing of the fuel injector, for example. It makes use of a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If either of these go badly, you will see codes on the diagnostic scanner that could cause engine shut down.

Some of the signs of a malfunctioning G28 sensor audi a1 Keys are an inaccurate rev counter in the gearbox the gears are shifting faster than normal, and/or a misfire when in gear. It is probable that your sensor is failing and needs to be replaced if you notice any of these symptoms. The good news is they are very cheap and easily accessible, especially in the case of an Bosch sensor, which is what ours are. Alternately, the GM version of this part is also a good choice.

5. Tachometer

A malfunctioning engine sensor can cause a number of problems in your car. It's an essential component of the transmission of your audi key Replacement Cost, as it transmits information to the ECU regarding how fast or slowly the engine is spinning. This sensor could cause the transmission to fail and other car components to be affected.

The G5 engine speed sensor is located on the outside of the transmission just above the flywheel ring gear and sends a signal to the ECU at pin T55/49 via a grey wire. The ECU is then able to process this signal to control the flow of fuel, timig and boost as well as transmitting it to the G5 tachometer in the instrument cluster. You can check the sensor for any failure by checking the continuity between it and the tachometer, between the ECU pin T55/49 and the instrument cluster connection via pin T6a/1 (trace [79trace [79]) and between pin T6a/1 and the instrument cluster pin T26a/12. It should show around 1000 ohms of resistance between those two pins. This is a typical part that is found across the audi key 80, 100 200, UrS and RS2 range from 1985 MC until the 1997 UrS AAN and 1995 RS2 ADU, so the best parts could be found in wrecking yards.