How to Replace an Replacement Audi Key Cost G28 Engine Speed Sensor
Charles the Humble Technician shows you how to replace the G28 Engine Speed Sensor. This sensor is located near the transmission’s edge, above the flywheel gear. It sends a signal to the ECU via an uncolored wire (T55/49) which is then sent to the tachometer in the instrument cluster.
1. Engine Speed Sensor
The sensor is located at the edge of the transmission just above the flywheel ring gear the G28 Engine Speed Sensor sends an electrical signal to ECU pin T55/49 using the grey wire. The ECU then utilizes this information to regulate the flow of fuel, timig and boost. It also sends an alert to the G5 Tachometer within the instrument cluster.
The sensor is used as a reference to correlate with the G40 Camshaft Position Sensor. The ecu must know when the crankshaft reached TDC and also the position of the camshaft, in order to activate the spark and injectors.
If this sensor fails, the ECU will display an error code P00160. This indicates that the Crank Shaft is out of sync with the Intake Camshaft. It could also be a sign of the possibility of a chain stretch or jump in the chain link of the upper chain. However the code will not appear on its own without additional information from other sensors (G4 and G40).
Testing is a bit challenging as there are two different connector pins and they have different functions however the best method to test it is to measure the resistance between the sensor and the ECU. When the sensor is operational, it should be reading approximately 1000 ohms. If you’re having issues with this sensor, look for evidence of coolant or oil in the connector bay.
2. Injectors
Yesterday, when i was accelerating to the fullest speed from highway paytoll, i experienced a big cut in power as if the engine was running out of gas or the injectors aren’t firing anymore. Today, i pulled out the spark plugs, three were soaked with gazoline and the 4th one was dry. I put a piece of tissue over each injector hole, and when I start the engine with no sparks, the three with gazoline jump out. The 4th one remains closed. I tried to test the ground connections of ECU pins 14,30 and 48/55. I found 0ohm. So i assume the problem is in another place.
I also tried to reset the PID without success. The car can start when the G28 is unplugged and is running fine when it is connected, but still has intermittent misfire issues at higher RPM. The temperature sensor for the coolant (G62) shows the wrong temperature of that is -49c even after unplugging it. Also, i noticed that the gauge for oil pressure in the cockpit is showing 2 bar while the actual pressure is 0.0 when i rev the engine.
I’m not certain what to do, as i believe that i’ve ruled out everything else. I’m afraid i may have missed something. If anyone has suggestions, please let me know! TIA!
3. Fuel Pump
The fuel pump on the g28 is activated by a signal sent by the RPM sensor. The GM-style sensor is identical to the G4 and both are used in the 80, 100, 200, UrS and RS2 cars which is why you can easily locate one at a salvage yard or at a parts store. It is simple to test them – simply switch your DMM into resistance mode and measure the distance between pins 1 and 2 (with the bump on the connector’s edge facing upwards). 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 position and speed of the crankshaft in order to make a decision about timing of the fuel injector, for example. It utilizes a Crank Position Sensor G4 and an Engine Speed Sensor G28 to achieve this. If you have a problem with either of these sensors, the diagnostic scanner will display codes that could lead to the engine shutting down.
The signs of a malfunctioning G28 sensor are an inaccurate rev counter for the gearbox, gears shifting quicker than normal and/or misfiring when you are in gear. It is likely that the sensor is failing and requires to be replaced if you notice any of these signs. The good thing is that they are quite affordable and easy to find, especially in the audi tt key case of an Bosch model, which is what we have. Alternately, the GM version of this unit is also a great option.
5. Tachometer
A malfunctioning engine sensor can cause a variety of issues in your car. It’s an essential component of the transmission in your audi a3 key fob replacement because it relays information to the ECU on how fast or slow the engine of the car is spinning. If the sensor fails, it can affect the performance of the transmission, as well as the rest of the car’s components.
The G5 engine sensor is located at the outskirts of the transmission, over the flywheel ring. It transmits an electrical signal through gray wire to ECU pin T55/49. The ECU is then able to process the signal to control fuel, timig and boost and then transmitting it to the G5 tachometer inside the instrument cluster. You can check the sensor for failure by examining the continuity between it and the tachometer, between ECU pin T55/49 and the instrument cluster connection via pin T6a/1 (trace [79trace [79]) and between pin T6a/1 and the instrument cluster pin T26a/12. You should see a resistance of approximately 1000 ohms between these points. This is a typical part across the audi key replacement 80, 100, 200, UrS and RS2 range from 1985 MC until the 1997 UrS AAN and 1995 RS2 ADU. Good ones could be available in wrecking yards.