25 Unexpected Facts About Audi G28

How to Replace an audi key fob not working G28 Engine Speed Sensor

In this video, Charles the Humble Mechanic demonstrates how to replace the G28 engine speed sensor. This sensor is located at the edge of transmission just above the flywheel gear. It transmits a signal to the ECU via the grey wire T55/49 and 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 the G28 Engine Speed Sensor key audi - click the next web site, sends a signal to ECU pin T55/49 using the grey wire. The ECU then utilizes this information to regulate fuel, timig and boost. It also sends an alert to the G5 Tachometer within the instrument cluster.

The sensor is used to link 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 chain of timing. However, the code won't appear on its own, without additional information from other sensors (G4 and G40).

It can be a bit difficult to test as there are various connector pins, and each has its own 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 read around 1000 ohms. If you're experiencing issues with this sensor, look for signs of oil or coolant in the connector bay.

2. Injectors

Yesterday, when accelerating from highway paytoll at maximum speed I noticed a significant reduction in power. It was as if the engine was running out of gas. Or, my injectors were not firing. I pulled out the spark plugs this morning, three were soaked in gasoline, and the 4th was dry. I put tissue over each hole in the injector and when i turn the engine on without sparks, the ones that have gazoline pop right out. The 4th one stays closed. 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 elsewhere.

I also tried to reset the PID but with no luck. The car will start when the G28 is unplugged, and it is running fine with the G28 connected. However, the intermittent misfire problem still occurs at higher RPM. The coolant sensor (G62), even when unplugged, still shows temperatures of -49c. I also noticed that the oil pressure gauge in the cockpit is showing 2 bar, whereas the actual pressure is 0.0 when i rev the engine.

I'm not certain what to do, as 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 on the g28 is activated by a signal sent from the RPM sensor. The GM-style transmitter is identical to the G4 and both are used in the 80, 100, 200, UrS and RS2 cars so you can easily find one at a salvage yard or in a local parts store. It is easy to test them: simply put your DMM into resistance mode and determine the distance between pins 1 and 2 (with the bump at the connector end facing upwards). 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 position and speed of the crankshaft to make decisions regarding fuel injector timing etc. To accomplish this, it makes use of a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If either of these go wrong, you will receive codes on the diagnostic scanner which can lead to engine shutdown.

Some of the signs of a failing G28 sensor cheap are an inaccurate rev counter in the gearbox the gears are shifting faster than normal and/or a misfire when you're in gear. If you experience any of these issues, it is most likely that your sensor is going bad and needs replacing. The good news is they are very cheap and easily accessible, especially in the case of the Bosch model, which is what ours are. Alternately, GM's version this part is an option.

5. Tachometer

A failing engine sensor could cause a number of problems within your vehicle. It's a crucial component of the transmission of your audi a3 key fob replacement since it sends information to the ECU on how fast or slow the engine of the car is spinning. This sensor could cause the transmission to fail and other components of the car to be affected.

The G5 engine speed sensor is situated on the edge of the transmission above the flywheel ring gear and sends a signal to the ECU at pin T55/49 via a grey wire. The ECU utilizes this signal to regulate the amount of fuel and boost, and also to timigrate. It also relays it to the G5 Tachometer located in the instrument cluster. You can test for sensor failure by checking 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. There should be the resistance to be around 1000 ohms between these points. This is a typical part that is found across the audi New Key 80 100 200, UrS and RS2 range from 1985 MC to the 1997 UrS AAN and 1995 RS2 ADU so good ones could be available in wrecking yards.