What You Must Forget About Improving Your Audi G28

How to Replace an audi a3 spare key G28 Engine Speed Sensor

Charles the Humble Technician teaches you how to replace the G28 Engine Speed Sensor. The sensor is located at the edge of transmission, above the flywheel gear. It sends a message to the ECU via a grey wire T55/49, then to the tachometer In my area the instrument cluster.

1. Engine Speed Sensor

The grey wire is situated on the outside of the transmission, directly above the flywheel ring. The sensor transmits a signal via the grey wire to pin T55/49. The ECU utilizes this information to regulate boost and fuel. It also sends an alert to the G5 Tachometer within the instrument cluster.

The sensor is used to correlate 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 trigger spark and injectors accordingly.

If this sensor fails, the ECU will display an error code P00160. This means that the Crank Shaft is not in alignment with the Intake Camshaft. It could also be a sign of a chain stretch or a jump in the chain link of the upper chain of timing. The code will not appear without the additional information provided by other sensors (G4 or G40).

It is a little tricky to test since there are different 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. It should read around 1000 ohms when it is operating at its maximum. Look for signs of coolant, or oil in the connector bay if you are experiencing issues with this part.

2. Injectors

Yesterday, as i was accelerating off the highway paytoll at a high speed I noticed a significant decrease in power. It was as if the engine had run out of gas. Or my injectors weren't firing. I pulled out the spark plugs this morning and found that 3 were drenched in gasoline and the 4th was dry. When I start the engine with no sparks, I put a piece of tissue on the top of each hole in the injector and the 3 that were drenched in gazoline jump out but the 4th stays closed. I tested the ground connection on ECU pins 14/55,30/55 and 48/55 i get zero ohm. So i assume the problem is in another place.

I also tried to reset the PID with no success. The car will start when the G28 is unplugged, and it is running fine with the G28 connected. However the intermittent misfire issue continues to occur at higher RPM. The coolant sensor (G62), even if it is not plugged in, shows temperatures of -49c. I also noticed that the oil gauge in the cockpit shows 2 bars while the actual pressure is 0.

I'm not certain what to do, i believe that i've ruled out everything else. I'm afraid i may have missed something. Let me know if you have any ideas! TIA!

3. Fuel Pump

The fuel pump in the g28 gets a signal from the RPM sensor. The GM-style transmitter functions similarly to the G4 sender, and both operate on the 80,100,200, UrS, and RS2 vehicles. It is easy to find a spare in a wrecking shop or a parts store. It is simple to test them by putting your DMM in resistance mode and measure between pins 1 (with the bump on the connector end up) and 2 (2nd from left on the black end of the connector). They must be infinite ohms.

4. ECU

The ECU of our 20vt turbo (3B AAN ABY) engines needs to be aware of the position and speed the crankshaft to determine timing of the fuel injector, etc. In order to do this it uses a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If you are experiencing issues with either of these sensors, the diagnostic scanner will display the codes that could trigger the engine shutting down.

A failing G28 sensor could result in an inaccurate speed counter for your gearbox, a gearbox that shifts more quickly than normal, and/or an unfire when in gear. If you are experiencing any of these issues, Audi spare key it is likely that your sensor is failing and should be replaced. The good thing is that they are very cheap and easy to find particularly when you're looking at an Bosch sensor, like ours. Alternately, the GM version of this component is also a good option.

5. Tachometer

A failing engine speed sensor could be the cause of numerous problems in your car. It's a vital component of the audi key fob replacement cost's transmission as it sends information to the ECU about how the car's crankshaft is rotating. This sensor could cause the transmission to malfunction and other car components to be affected.

The G5 engine speed sensor is located at the edge of the transmission just above the flywheel ring gear and sends a signal directly to the ECU at pin T55/49 through an uncolored wire. The ECU uses this signal to regulate the flow of fuel and boost as well as timig. It also relays it to the G5 Tachometer in instrument cluster. You can check 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. You should see approximately 1000 ohms of resistance between these two points. This is a typical component across the audi car key 80, 100, 200, UrS and Audi Spare Keys RS2 range from 1985 MC through the 1997 UrS AAN and 1995 RS2 ADU, so the best ones could be available in wrecking yards.