How to Replace an Audi G28 Engine Speed Sensor
Charles the Humble Technician shows you how to replace the G28 Engine Speed Sensor. This sensor is situated near the transmission's edge, above the flywheel gear. It transmits a signal to the ECU via the grey wire (T55/49) which is then sent to the tachometer in the instrument cluster.
1. Engine Speed Sensor
It is located on the outside of the transmission above the flywheel ring gear G28 Engine Speed Sensor sends signals to ECU pin T55/49 through the grey wire. The ECU utilizes this information to regulate boost and fuel. It also sends an indication to the G5 Tachometer located in the instrument cluster.
The sensor is used to connect with the G40 Camshaft position Sensor. The ecu must be aware of when the crankshaft has reached TDC, and where the camshaft lies in order to activate the spark and injectors.
If this sensor fails the ECU will display the P00160 error, which means the Crank Shaft and Intake Camshaft are out of sync and possibly indicating the chain stretching or a jump link on the upper chain of timing. The code will not appear without the additional information provided by other sensors (G4 or G40).
It can be a bit difficult to test as there are several pins on the connector and they all have different functions. The best way to do it is by measuring the resistance between the ECU and the sensor. It should read approximately 1000 ohms when the sensor is operating at its maximum. If you're experiencing issues with this part, check for evidence of oil or coolant in the connector bay.
2. Injectors
Yesterday accelerating full speed from highway paytoll, I experienced massive power loss as if the engine was running out of gas or the injectors are not firing any more. I took out the spark plugs this morning, 3 were soaked in gasoline, and the 4th was dry. I placed a tissue over each injector hole, and when i start the engine with no sparks, the ones with gazoline jump out. The 4th one stays shut. I checked the ground connection on ECU pins 14/55,30/55 and 48/55 I get zero Ohm. I'm assuming the issue is in another place.
I also tried to reset audi a3 key replacement near me the PID but without success. The car will start if the G28 is unplugged and runs fine when it is connected, but still is experiencing intermittent misfires at higher RPM. The coolant temperature sensor (G62) shows read more the wrong temperature of that is -49c even after unplugging it. 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 sure what to do. I feel like i've pretty much ruled everything else out. However, i'm afraid that I may have missed something. If anyone has any ideas please let me know! TIA!
3. Fuel Pump
The fuel pump of the g28 receives signals 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. You can easily locate the spare in a salvage shop or a parts store. It is easy click here to test them: simply put your DMM into resistance mode and test the distance between pins 1 and 2 (with the bump at the connector's end facing upwards). They should be infinite ohms.
4. ECU
The ECU in our 20vt turbo (3B AAN ABY ADU) engines requires to be aware of the position and speed of the crankshaft to determine fuel injector timing, etc. It makes use of a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If either of these goes click here badly, you will see codes on the diagnostic scanner that could cause engine shut down.
A damaged G28 sensor can cause an inaccurate speed counter for your gearbox or a gearbox that shifts faster than normal, and/or a misfire in gear. If you experience any of these issues it is most likely that your sensor is going bad and should be replaced. They're inexpensive and easy to locate especially if they're a Bosch sensor like ours. Alternately, GM's version this part is a good option.
5. Tachometer
A malfunctioning engine speed sensor could be a cause for many issues in your vehicle. It's an essential component of the transmission in your Audi, as it transmits information to the ECU on how fast or slowly the car's engine is turning. This sensor can cause the transmission to fail and other components of the car to be affected.
The G5 engine speed sensor is located at the outside 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 is then able to process this signal to control fuel, timig and boost, and also transmitting it to the G5 tachometer in the instrument cluster. You can check for sensor failure by checking continuity from the sensor to the tachometer. You can also audi key replacement check continuity between pin 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 see a resistance of approximately 1000 ohms in these areas. This is a common feature across the Audi 80-100-200-RS2 series, starting beginning with the 1985 MC and up to the 1997 UrS AN and 1995 RS2 DU You may also find them in wrecking yards.