How to Replace an
audi key Shell G28 Engine Speed Sensor
In this video Charles the Humble Mechanic demonstrates how to replace the G28 engine speed sensor. This sensor is situated near the transmission's edge just above the flywheel gear. It transmits a signal to the ECU through the grey wire T55/49 and then to the tachometer located on the instrument cluster.
1. Engine Speed Sensor
The grey wire is situated on the outside of the transmission, just above the flywheel ring. The sensor sends signals through the grey wire to pin T55/49. The ECU then uses this information to control the boost, fuel, and timig. It also sends an indicator to the G5 Tachometer in instrument cluster.
The sensor is used to link the G40 Camshaft position Sensor. The ecu needs to be aware of when the crankshaft has reached TDC, and the position of the camshaft, in order to activate the spark and injectors.
If this sensor fails, the ECU will display a P00160 error code. This indicates that the Crank Shaft is not in alignment with the Intake Camshaft. It could also be a sign of the possibility of a chain stretch or jumped chain link in the upper chain. The code won't appear without the additional information provided by other sensors (G4 or 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 by measuring resistance between the sensor and the ECU. If the sensor is operational, it should be reading about 1000 ohms. Examine for signs of coolant, or oil in the connector bay if you have issues with this part.
2. Injectors
Yesterday accelerating full speed from highway paytoll, I experienced a big cut in power like the engine is out of gas or injectors are not firing anymore. I took out the spark plugs this morning and found that 3 were drenched in gasoline and the fourth was dry. I placed a tissue over each hole in the injector and when I turn the engine on without sparks, the three that have gazoline pop right out. The 4th one remains closed. I tested the ground connection of ECU pins 14,30, and 48/55. I found zero ohm. I assume that the problem is in another location.
I also tried to reset PID without success. The car will start when the G28 is disconnected, but it is running fine with the G28 plugged in. However the intermittent misfire issue persists at higher RPM. The coolant sensor (G62), even when it is unplugged, shows an ice temperature of -49c. I also noticed that the oil gauge in the cockpit shows 2 bar while the actual pressure is zero.
I'm not sure what to do. I think I've eliminated everything else. I'm worried that i might have missed something. If anyone has any suggestions, please let me know! TIA!
3. Fuel Pump
The fuel pump on the g28 is activated by a signal by the RPM sensor. The GM-style transmitter is similar to the G4 sender and both work on the 80,100,200, UrS, and RS2 vehicles. It is easy to find the spare in a salvage shop or parts store. Test them out by putting your DMM in resistance mode and measure between pins 1 (with the bump on the connector end up) and 2 (2nd from the left on the black connector's side). They should be infinite ohms.
4. ECU
Our 20vt turbo (3B, AAN, ABY and ADU) engines have an ECU that needs to know the speed and position of the crankshaft in order to make decisions regarding timing of the fuel injector, for example. To accomplish this, it makes use of a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If you are experiencing issues with either of these sensors, the diagnostic scanner will show the codes that could trigger an engine shut down.
Some of the symptoms of a malfunctioning G28 sensor include an inaccurate rev counter for the gearbox, gears shifting quicker than normal, and/or a misfire when in gear. If you experience any of these problems, it is likely that your sensor is failing and should be replaced. They're cheap and easy to find particularly when they're a Bosch model like ours. Alternately, the GM version of this unit is also a good choice.
5. Tachometer
A failing engine speed sensor could be the reason behind numerous issues in your vehicle. It's a crucial component of the transmission of your
audi key since it sends information to the ECU on how fast or slowly the car's engine is spinning. This sensor could cause the transmission to fail and other car components to be affected.
The G5 engine speed sensor is situated on the outside of the transmission above the flywheel ring gear. It transmits a signal to the ECU at pin T55/49 through a grey wire. The ECU uses this signal to regulate fuel and boost, and also to timigrate. It also sends it to the G5 Tachometer located in the instrument cluster. You can test the sensor for
Replacement Key For Audi A4 failure by examining the continuity between it and the tachometer, between ECU pin T55/49 and the instrument cluster connection on pin T6a/1 (trace [79trace [79]) and between pin T6a/1 and the instrument cluster pin T26a/12. You should detect a resistance of approximately 1000 ohms between these two points. This is a common feature across the
new audi key 80-100-200-RS2 series,
Audi key Fob 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.