How to Replace an Audi G28 Engine Speed Sensor
In this video, Charles the humble mechanic demonstrates how to replace the G28 engine speed sensor. The sensor is situated near the edges of the transmission just above the flywheel ring gear. It transmits a signal to the ECU through a grey wire T55/49, then to the tachometer located on 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 via the grey wire. The ECU uses this information to regulate the amount of fuel and boost. It also sends an indication to the G5 Tachometer located in the instrument cluster.
The sensor serves as a reference for comparing with the G40 Camshaft Position Sensor. The ecu must be aware of when the crankshaft has reached TDC and also the location of the camshaft to trigger the spark and injectors.
If this sensor fails, the ECU will throw 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 timing chain. However the code will not appear on its own without additional information from other sensors (G4 and G40).
Testing can be a bit difficult as there are two different connector pins, and they have different functions but the most effective method of testing it is to measure resistance between the sensor and the ECU. It should read about 1000 ohms when it is at full operation. Look for signs of coolant or oil in the connector bay if there are problems with this part.
2. Injectors
Yesterday, when accelerating from highway paytoll at maximum speed, i noticed a huge reduction in power. It was like the engine had run out of gas. Or my injectors were not firing. In the morning, i removed the spark plugs, three were drenched with gazoline the 4th one was dry. When i crank the engine, there are no sparks i put tissue on the top of each of the injector holes and the 3 that were drenched in gazoline jump out but the 4th one stays closed. I tried to test the ground connections of ECU pins 14,30 and 48/55. I got 0ohm. I'm assuming the issue is in another place.
I also tried to reset the PID but without success. The car can start when the G28 is not plugged in and runs fine when it is connected but it still is experiencing intermittent misfires at higher RPM. The coolant sensor (G62), even when unplugged, still shows temperatures of -49c. I also noticed that the oil gauge in the cockpit shows 2 bar while the actual pressure is 0.
I'm not certain what to do, as i believe that i've completely ruled out all other possibilities. I'm afraid i may have missed something. Please let me know If you have any suggestions! TIA!
3. Fuel Pump
The fuel pump in the g28 is activated by 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. You can easily locate the spare in a salvage shop or a parts store. It is simple to test them to do - just put your DMM in resistance mode and measure the website resistance between pins 1 (with the bump on the connector end up) and 2 (2nd from left on the black connector's side). They should be infinite ohms.
4. ECU
The ECU of our 20vt turbo (3B AAN ABY ADU) engines needs to be aware of the speed and position of the crankshaft in order check here to make a decision about timing of fuel injectors, etc. To do 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 cause the engine to shut down.
The signs of a malfunctioning G28 sensor here are an inaccurate rev counter for the gearbox and gears that shift faster than normal, and/or a misfire when in gear. If you are experiencing any of these issues it is likely that your sensor is deteriorating and should be replaced. They're cheap and easy to find especially in the case of an Bosch sensor like ours. Alternately, GM's version this part is a good option.
5. Tachometer
A faulty engine speed sensor could be the cause of numerous issues with your car. It is a crucial part of the Audi's transmission as it sends information to the ECU about how fast or slow the car's crankshaft is rotating. If the sensor fails, it will cause problems for the transmission, as well as the other car's components.
The click here G5 engine speed sensor is located at the outside of the transmission just above the flywheel ring gear. It sends a signal to the ECU at pin T55/49 via an uncolored wire. The ECU uses this signal to control the flow of fuel and boost as well as timig. It also sends it to the G5 Tachometer in instrument cluster. You can test the sensor for any failure by checking the get more info continuity between it and the tachometer. You can also check continuity between ECU pin T55/49 and the instrument cluster connection to pin T6a/1 (trace [79]) and between T6a/1 and the instrument cluster pin T26a/12. There should be the resistance to be around 1000 ohms between these two points. 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 the 1995 RS2 Du So, you may find some good ones in wrecking yards.