Why No One Cares About Audi G28

How to Replace an audi q5 key G28 Engine Speed Sensor

In this video, Charles the humble mechanic demonstrates how to replace the G28 engine speed sensor. This sensor audi key programming (https://moses-lindberg-4.technetbloggers.de/The-Most-hilarious-complaints-Weve-received-about-audi-keys) is situated near the transmission's edge, above the flywheel gear. It transmits a signal to the ECU through the grey wire T55/49 and then to the tachometer in the instrument cluster.

1. Engine Speed Sensor

The grey wire is situated on the outside of the transmission, audi key fobs just above the flywheel ring. The sensor transmits a signal via the grey wire to pin T55/49. The ECU uses this information to regulate the amount of fuel and boost. It also sends an indication to the G5 Tachometer in instrument cluster.

The sensor is used as a reference point to connect with the G40 Camshaft Position Sensor. The ecu needs to know when the crankshaft is TDC and the location of the camshaft so it can start spark and injectors in the right way.

If this sensor fails the ECU will show an error code P00160 which indicates that the Crank Shaft and Intake Camshaft are not in sync and could indicate chain stretch or a jumped 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 can be a bit difficult to test since there are several connector pins, and each one has different functions. The best way to do it is by measuring the resistance between the ECU and the sensor. When the sensor is fully functional, it should read about 1000 ohms. If you're having issues with this part, check for evidence of oil or coolant in the connector bay.

2. Injectors

Yesterday, while accelerating at full speed from the highway paytoll i had an abrupt drop in power like the engine is running out of gas or the injectors aren't firing any more. I took out the spark plugs this morning, 3 were soaked with gasoline and the 4th was dry. When i crank the engine, there are no sparks i put tissue on the top of each hole in the injector, the 3 drenched with gazoline pop out, but the 4th stay shut. I tried to test the ground connections of ECU pins 14,30, and 48/55. I got zero ohm. I'm assuming that the issue is elsewhere.

I also tried to reset the PID with no success. The car will start if the G28 is unplugged and is running fine when it is connected, but still has intermittent misfire issues at higher RPM. The coolant sensor (G62), even when unplugged, still shows an ice temperature of -49c. Also i noticed that the gauge for oil pressure in the cockpit shows 2 bar, whereas the actual pressure is 0.0 when i rev the engine.

I'm not certain what to do, but i believe that i've eliminated everything else. I'm worried that i might have missed something. If anyone has suggestions, please share them! 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 the same as 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 junkyard or in a local parts store. It is easy to test them - just put your DMM into resistance mode and determine the distance between pins 1 and 2 (with the bump on the connector's edge facing up). They must be infinite ohms.

4. ECU

Our 20vt turbo (3B, AAN, ABY and ADU) engines are equipped with an ECU that must be aware of the speed and position of the crankshaft to make a decision about timing of the fuel injector, for example. It makes use of a Crank Position Sensor G4 and an Engine Speed Sensor G28 to achieve this. If you have a problem with either one of these, the diagnostic scanner will show codes that could cause an engine shutdown.

Some of the signs of a malfunctioning G28 sensor are an inaccurate rev counter for the gearbox the gears are shifting faster than normal, and/or a misfire when in gear. If you experience any of these issues, it is most likely that your sensor is failing and should be replaced. The good news is that they are very cheap and readily available particularly when you're looking at the Bosch sensor, like ours. Alternately, GM's version this component is an option.

5. Tachometer

A malfunctioning engine sensor can cause a number of problems in your vehicle. It is a crucial part of the audi q7 key's transmission because it communicates to the ECU about how fast or slow the vehicle's crankshaft is spinning. When this sensor fails, it will 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 above the flywheel ring gear and transmits a signal to the ECU at pin T55/49 via an uncolored wire. The ECU uses this signal to control the amount of fuel and boost, and also timig. It also sends it to the G5 Tachometer in instrument cluster. You can determine if the sensor is in failure by checking continuity from the sensor to the tachometer. Also, you can verify continuity between pin T55/49 of the ECU and pin T6a/1 of the instrument cluster (trace [79]) and between pin T6a/1 and pin T26a/12. You should observe around 1000 ohms of resistance between those two pins. This is a standard part that is found across the audi replacement key cost 80, 100, 200, UrS and RS2 range from 1985 MC until the 1997 UrS AAN and 1995 RS2 ADU. Good parts could be found in wrecking yards.