20 Myths About Audi G28: Dispelled

How to Replace an audi key replacement G28 Engine Speed Sensor

Charles the Humble Technician teaches you how to replace audi key fob the G28 Engine Speed Sensor. The sensor is situated on the edge of the transmission above the flywheel ring gear. It sends a message to the ECU via a grey wire T55/49, then to the tachometer on the instrument cluster.

1. Engine Speed Sensor

The grey wire is located at the edges of the transmission, above the flywheel ring. The sensor sends an electrical signal through the grey wire to pin T55/49. The ECU utilizes this information to regulate the amount of fuel and boost. It also sends an alert to the G5 Tachometer within the instrument cluster.

The sensor serves as a reference for comparing with the G40 Camshaft Position Sensor. The ecu has to know when the crankshaft reached TDC and also where the camshaft lies to trigger the spark and injectors.

If this sensor audi a1 Key fails to function, the ECU will display a P00160 error code. This indicates that the Crank Shaft is out of alignment with the Intake Camshaft. It could also indicate the possibility of a chain stretch or jumpy chain link in the upper timing chain. However, the code won't appear on its own, without additional information from other sensors (G4 and G40).

Testing is a bit challenging since there are two connector pins, and they have different functions however the best method of testing it is to measure resistance between the sensor and the ECU. If the sensor is functional, it should read about 1000 ohms. Look for evidence of coolant or oil in the connector bay if you have problems with this part.

2. Injectors

Yesterday, while accelerating at full speed from the highway paytoll, I experienced a big cut in power like the engine is running out of gas or the injectors aren't firing any more. I pulled out the spark plugs this morning, three were drenched in gasoline and the fourth was dry. When i crank the engine with no sparks, I put a piece of tissue on the top of each of the injector holes and the 3 that were drenched in gazoline pop out, but the 4th one stays shut. I inspected the ground connection on ECU pins 14/55/30/55/48/55/14/55/48/ I get zero Ohm. So i assume the problem is in another place.

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

I don't know what to do. I think I've eliminated everything else. However, i'm afraid that I may have missed something. Please let me know should you have any suggestions! TIA!

3. Fuel Pump

The fuel pump of the g28 receives signals from the RPM sensor. The GM-style transmitter is similar to the G4 sender and both work on the 80,100,200, UrS, and RS2 vehicles. You can easily find the spare in a salvage shop or a parts store. Testing them is easy - 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 left on the black end of the connector). They should 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 decisions about fuel injector timing etc. It uses a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If either of these goes wrong, you will receive codes on the diagnostic scanner that could cause engine shut down.

Some of the symptoms of a failing G28 sensor include an inaccurate gearbox rev counter the gears are shifting faster than normal, and/or a misfire when you're in gear. If you have any of these issues, it is likely your sensor is deteriorating and requires audi tt replacement key. The good thing is that they are very cheap and readily available, especially if you're looking at a Bosch unit which is what we have. Alternatively, GM's version of this part would be a good option.

5. Tachometer

A malfunctioning engine speed sensor could be the cause of many problems in your vehicle. It's a crucial component of the transmission of your audi tt key fob not working since it sends information to the ECU on how fast or slowly the car's engine is spinning. If the sensor fails, it will cause problems for the transmission, as well as the other car's components.

The G5 engine sensor is located at the edge of the transmission, over the flywheel ring. It sends signals via gray wire to ECU pin T55/49. The ECU is then able to process this signal to regulate the flow of fuel, timig and boost as well as transmitting it to the G5 Tachometer located in the instrument cluster. You can test the sensor for failure by checking 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. It should show around 1000 ohms of resistance between those points. This is a typical part across the key audi 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.