How to Replace an Audi G28 Engine Speed Sensor
Charles the Humble Technician shows how to replace the G28 Engine Speed Sensor. This sensor is located near the edges of the transmission above the flywheel ring gear. It transmits a signal to the ECU via a grey wire (T55/49) and then to the tachometer within the instrument cluster.
1. Engine Speed Sensor
The grey wire is situated on the edge of transmission, above the flywheel ring. The sensor transmits a signal via the grey wire to pin T55/49. The ECU utilizes this information to control the amount of fuel and boost. It also sends a signal to the G5 tachometer inside the instrument cluster.
The sensor is used to link the G40 Camshaft position Sensor. The ecu needs to know when the crankshaft is TDC and the location of the camshaft so it can start spark and injectors in the right way.
If this sensor fails to function, the ECU will display a P00160 error code. This means 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 will not appear without the additional information supplied by other sensors (G4 or G40).
Testing is a bit tricky because there are two connector pins and they perform different functions but the best way to test it is to measure resistance between the sensor and the ECU. It should read around 1000 ohms when it is operating at its maximum. If you are having problems with this component, look for signs of oil or coolant in the connector bay.
2. Injectors
Yesterday, while accelerating at full speed from the highway paytoll, I experienced massive power loss as if the engine was running out of gas or injectors are not firing any more. I took out the spark plugs this morning, three were soaked with gasoline and the fourth was dry. I placed a tissue over each injector hole, and when I turn the engine on without sparks, the 3 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 0ohm. Therefore, i think the issue is in another place.
I also tried to reset the PID without success. The car can start when the G28 is not plugged in and is running fine when it is connected, but still has intermittent misfire issues at higher RPM. The coolant temperature sensor (G62) shows the wrong temp value -49c even when i unplug it. I also noticed that the oil gauge in the cockpit shows 2 bar when the actual pressure is zero.
I'm not certain what to do, as i think i've pretty much eliminated everything else. I'm worried that i might have missed something. Please let me know if you have any ideas! TIA!
3. Fuel Pump
The fuel pump on the g28 is activated by a signal by the RPM sensor. The GM-style sender 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 wrecking yard or at a parts store. Testing them is easy to do - just put your DMM in resistance mode and measure between pins 1 (with the bump on the connector's end up) and 2 (2nd from the left on the black end of the connector). They must 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 decisions regarding timing of the fuel injector, for example. It makes use of a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If you are experiencing issues with either one of these, the diagnostic scanner will show the codes that could trigger an engine shut down.
A failing G28 sensor could result in an inaccurate speed counter for your gearbox, a gearbox that shifts faster than normal, or a misfire while in gear. It is possible that the sensor is failing and requires to be replaced if you experience any of these symptoms. They're audi car keys cheap and easy to find especially in the case of a Bosch model like ours. Alternately, GM's version this part would be an option.
5. Tachometer
A failing engine sensor could cause a number of problems in your vehicle. It is an important part of the transmission in your Audi since it sends information to the ECU regarding how fast or slow the engine of the car is spinning. This sensor could cause the transmission to fail and other components in the car to be affected.
The G5 how to open audi car key engine speed sensor is located on the edge of the transmission, above the flywheel ring gear and transmits a signal to the ECU at pin T55/49 through an uncolored wire. The ECU then uses and processes this signal audi keys replacement to control fuel, timig, and boost and then transmitting it to the G5 tachometer inside the instrument cluster. You can test the sensor for any failure by checking the continuity between it and the tachometer, between the ECU pin T55/49 and the instrument cluster connection to pin T6a/1 (trace [79]) and between T6a/1 check here and the instrument cluster pin T26a/12. There should be an average resistance of 1000 ohms between these two points. This is a common component across the Audi 80, 100 200, UrS and RS2 range from 1985 MC through the 1997 UrS AAN and 1995 RS2 ADU, so the best parts could be get more info found in wrecking yards.