10 Quick Tips About Audi G28
10 Quick Tips About Audi G28
Blog Article
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 located on the edge of the transmission just above the flywheel ring gear. It sends a message to the ECU through the grey wire T55/49 and then to the tachometer in the instrument cluster.
1. Engine Speed Sensor
The grey wire is situated on the outside of the transmission, directly above the flywheel ring. This sensor sends signals through the grey wire to pin T55/49. The ECU utilizes this information to regulate boost and fuel. It also sends a signal to the G5 tachometer in the instrument cluster.
The sensor is used to correlate with the G40 Camshaft position Sensor. The ecu must know when the crankshaft has reached TDC, and where the camshaft lies in order to activate the spark and injectors.
If this sensor fails when it fails, the ECU will display a P00160 error message. This indicates that the Crank Shaft is not in line with the Intake Camshaft. It could also indicate a chain stretch or a jumpy chain link in the upper timing chain. The code won't appear without the additional information supplied by other sensors (G4 or G40).
Testing can be a bit difficult as there are two different connector pins, and they have different functions but the most effective method to test it is to measure resistance between the sensor and the ECU. When the sensor is operational, it should read about 1000 ohms. Look for signs of coolant, or oil in the connector bay if you have issues with this component.
2. Injectors
Yesterday, while accelerating from the highway paytoll at full speed I noticed a massive drop in power. It was like the engine had run out of gas. Or my injectors were not firing. I took out the spark plugs this morning, 3 were drenched in gasoline and the fourth was dry. I put a piece of tissue over each hole in the injector and when I turn the engine on without sparks, the 3 with gazoline jump right out. The fourth one remains closed. I tried to test the ground connections of ECU pins 14,30, and 48/55. I found zero ohm. I'm assuming the issue is somewhere else.
I also tried to reset the PID without success. The car is able to start if the G28 is unplugged and runs fine when it is connected but it still has the intermittent misfire issue at higher RPM. The coolant sensor (G62) even when it is unplugged, shows an ice temperature of -49c. I also noticed that the oil audi a5 replacement key gauge in the cockpit shows 2 bar when the actual pressure is zero.
I'm not sure what to do, as i believe that i've eliminated everything else. I'm concerned that i may have missed something. If anyone has any suggestions, please let me know! TIA!
3. Fuel Pump
The fuel pump in the g28 can be activated by a signal sent by the RPM sensor. The GM-style sensor is identical to the G4 and both function in the 80, 100 200, UrS and RS2 cars which is why you can easily locate one at a wrecking yard or in a local parts store. It is simple to test them - put your DMM in resistance mode and take measurements between pins 1 (with the bump on the connector end up) and 2 (2nd from left on the black connector's side). They must be infinite ohms.
4. ECU
The ECU in our 20vt turbo (3B AAN ABY) engines must know the position and speed the crankshaft to determine timing of the fuel injector, etc. To do this, it utilizes a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If either of these goes bad you will get codes on the diagnostic scanner that could cause engine shut down.
A failing G28 sensor can cause an inaccurate gearbox speed counter or a gearbox that shifts more quickly than normal, or a misfire while in gear. If you have any of these issues it is likely your sensor is going bad and needs replacing. They're inexpensive and easy to locate especially in the case of an Bosch model like ours. Alternately, GM's version this part is an option.
5. Tachometer
A failing engine speed sensor could be read more the cause of many issues with your car. It is an important part of the transmission of your Audi since it sends information to the ECU about how fast or slowly the engine is spinning. This sensor could cause the transmission to malfunction and other components in the car 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 to the ECU at pin T55/49, via a grey wire. The ECU utilizes here this signal to control the flow of fuel and boost and also to timigrate. It also sends it to the G5 Tachometer inside the instrument cluster. You can check for sensor failure by checking more info continuity from the sensor to the tachometer. Also, you can verify continuity between pin 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. It should show approximately 1000 ohms of resistance between those two pins. This is the more info same across the Audi 80-100-200-RS2 series, starting from the 1985 MC all the way up to the 1997 UrS AN and 1995 RS2 Du So, you may find good ones in wrecking yards.