How To Outsmart Your Boss On Audi G28

How to Replace an audi a4 key replacement G28 Engine Speed Sensor

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

1. Engine Speed Sensor

The grey wire is located at the edges of the transmission, just above the flywheel ring. This sensor sends an electrical signal through the grey wire to pin T55/49. The ECU then uses this information to control fuel, timig and boost. It also sends an indicator to the G5 Tachometer within the instrument cluster.

The sensor is used to connect with the G40 Camshaft position Sensor. The ecu must know when the crankshaft is TDC and where the camshaft is located so that it can start spark and injectors according to the situation.

If this sensor fails the ECU will display an error code P00160 which indicates that the Crank Shaft and Intake Camshaft are out of sync and possibly indicating chain stretch or a jumped link on the upper chain of timing. However, the error 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 way to test it is to measure the resistance between the sensor and the ECU. It should read around 1000 ohms when it is in full operation. Examine for evidence of coolant or oil in the connector bay if there are issues with this component.

2. Injectors

Yesterday, when accelerating from highway paytoll at maximum speed I noticed a massive decrease in power. It was like the engine had run out of gas. Or, my injectors weren't firing. I took out the spark plugs this morning and found that 3 were soaked with gasoline and the 4th was dry. When I start the engine without sparks, i place a tissue on the top of each hole in the injector and the 3 that were drenched in gazoline leap out, however the 4th stay shut. I tried to test the ground connections of ECU pins 14,30, and 48/55. I found zero ohm. Therefore, i think the issue is in another place.

I also tried to reset PID without success. The car will start when the G28 is unplugged, and it runs fine with the G28 plugged in. However the intermittent misfire issue still occurs at higher RPM. The coolant sensor (G62) even if it is not plugged in, shows temperatures of -49c. I also noticed that the gauge for oil pressure in the cockpit shows 2 bar while the actual pressure is 0.0 when i rev the engine.

I'm not sure what to do, as i think i've pretty much ruled out everything else. However, i'm afraid that I might have missed something. If anyone has any suggestions, please let me know! TIA!

3. Fuel Pump

The fuel pump of the g28 receives a signal from the RPM sensor. The GM-style transmitter is identical to the G4 sender, and both operate on the 80,100,200, UrS, and RS2 vehicles. It is easy to find an extra in a wrecking shop or a parts store. It is easy to test them: simply put your DMM into resistance mode and test the distance between pins 1 and 2 (with the bump on the connector's edge facing upwards). They should be infinite ohms.

4. ECU

The ECU in our 20vt turbo (3B AAN ABY ADU) engines needs to be aware of the speed and position of the crankshaft to make decisions regarding timing of the fuel injector, etc. It utilizes a Crank Position Sensor G4 and an Engine Speed Sensor G28 to achieve this. If either of these sensors go bad you will get codes on the diagnostic scanner which can cause the engine to shut down.

A failing G28 sensor can cause an inaccurate speed counter for your gearbox, a gearbox that shifts more quickly than normal, and/or an unfire when in gear. It is probable that your sensor is failing and needs to be replaced if you encounter any of these signs. The good news is they are very affordable and easy to find, especially in the case of a Bosch model, which is what we have. Alternately, the GM version of this component is also a great option.

5. Tachometer

A malfunctioning engine sensor can cause a myriad of issues in your vehicle. It's an essential component of your audi Tt replacement Key's transmission, since it relays information to the ECU about how fast or slow the car's crankshaft is rotating. This sensor can cause the transmission to fail and other components of the car to be affected.

The G5 engine sensor is located at the edge of the transmission, over the flywheel ring. It transmits signals via an uncolored wire to the ECU pin T55/49. The ECU then uses and processes this signal to regulate fuel, timig, replacement audi a4 key Key fob not working (https://images.google.com.pa) and boost as well as sends it on to the G5 tachometer in the instrument cluster. You can check for sensor failure by examining the continuity of the sensor to the tachometer. You can also 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 and pin T26a/12. You should detect an average resistance of 1000 ohms between these two points. This is the same across the audi keyless entry 80-100-200-RS2 range, from the 1985 MC up to the 1997 UrS An and 1995 RS2 DU, so you might find some good ones in wrecking yards.