How to Replace an Audi G28 Engine Speed Sensor
Charles the Humble Technician shows you how to replace the G28 Engine Speed Sensor. This sensor is located at the top of the transmission, 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 located on the outside of the transmission, directly above the flywheel ring. The sensor sends signals through the grey wire to pin T55/49. The ECU utilizes this information to control the amount of fuel and boost. It also sends an indication to the G5 Tachometer in instrument cluster.
The sensor is used as a reference point to connect with the G40 Camshaft Position Sensor. The ecu must know when the crankshaft reached TDC, and where the camshaft lies in order to activate the spark and injectors.
If this sensor fails, the ECU will display a P00160 code which means the Crank Shaft and Intake Camshaft aren't in sync and could indicate the chain stretching or a jump link on the upper timing chain. The code won't show without the additional information supplied by other sensors (G4 or G40).
Testing is a bit tricky since there are two connector pins and they have different functions however the best way to test it is to measure resistance between the sensor and the ECU. It should read around 1000 ohms if the sensor is operating at its maximum. Examine for signs of coolant or oil in the connector bay if you have problems with this part.
2. Injectors
Yesterday, while accelerating at full speed from the highway paytoll, I experienced an abrupt drop in power like the engine is running out of gas or injectors are not firing any more. This morning i pull out the spark plugs, three were drenched in gazoline, the fourth was dry. When I crank the engine without sparks, I put a piece of tissue on top of each injector hole, the 3 drenched with 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. So i assume the problem is somewhere else.
I also tried to reset PID but without success. The car will start when the G28 is disconnected and it runs perfectly when it is plugged in, but still has intermittent misfire issues at higher RPM. The coolant sensor (G62) even if it is not plugged in, shows a temperature of -49c. Also, i noticed that click here the gauge for oil pressure in the cockpit is showing 2 bar while the actual pressure is 0.0 when I crank up the engine.
I'm not sure what to do. I think I've ruled everything else out. 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 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. It is easy to find the spare in a salvage shop or a parts store. Testing them is easy to do - just put your DMM in resistance mode and take measurements between pins 1 (with the bump on the connector's side 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 have an ECU that must know the position and speed of the crankshaft to make a decision about timing of the fuel injectors, etc. It utilizes a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If you have a problem with either of these, the diagnostic scanner will display the codes that could trigger an engine shut down.
Some of the symptoms of a audi car key failed G28 sensor are an inaccurate rev counter for the gearbox and gears that shift faster than normal and/or a misfire when in gear. If you have any of these issues it is likely that your sensor is failing and requires replacement. The good thing is that they are very here cheap and easily accessible particularly in the case of an Bosch sensor, which is what ours are. If you prefer, GM's version of this part is an option.
5. Tachometer
A malfunctioning engine sensor can cause a variety of issues in your vehicle. It is an important part of the transmission of your Audi because it relays information to the ECU on how fast or slow the engine of the car is spinning. This sensor can cause the transmission to fail and other components in the car to be affected.
The G5 engine sensor is located near the edge of transmission, above the flywheel ring. It sends signals via a gray check here wire to the ECU pin T55/49. The ECU uses this signal to regulate fuel and boost, and also timig. It also sends it to the G5 Tachometer located in the instrument cluster. You can test for sensor failure by examining the continuity of the sensor to the tachometer. Additionally, you can check continuity audi key replacement near me 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. There should be the resistance to be around 1000 ohms between these points. This is a standard component across the Audi 80, 100, 200, UrS and RS2 range from 1985 MC until the 1997 UrS AAN and 1995 RS2 ADU. Good ones might be availble in wrecking yards.