How to Replace an Audi G28 Engine Speed Sensor
Charles the Humble Technician teaches you how to replace the G28 Engine Speed Sensor. The sensor is located near the edges of the transmission above the flywheel ring gear. It transmits a signal to the ECU via an uncolored wire (T55/49), 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. The sensor sends signals through the grey wire to pin T55/49. The ECU utilizes this information to control fuel and boost. It also sends an alert to the G5 Tachometer in instrument cluster.
The sensor is used to correlate with the G40 Camshaft position Sensor. The ecu needs to know when the crankshaft has reached TDC and also the location of the camshaft so that it can activate the spark and injectors.
If this sensor fails to function, the ECU will display a P00160 error code. This indicates that the Crank Shaft is out of line with the Intake Camshaft. It could also indicate an issue with the chain or a jumped chain link in the upper 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 most effective way to test it is to measure the resistance between the sensor and the ECU. It should read approximately 1000 ohms if the sensor is at full operation. If you're experiencing issues with this component, look for evidence of oil or coolant in the connector bay.
2. Injectors
Yesterday, while accelerating from the highway paytoll at a high speed I noticed a significant reduction in power. It was like the engine had run out of gas. Or my injectors were not firing. I pulled out the spark plugs this morning, three were soaked with gasoline and the fourth was unclean. When i crank the engine with no sparks i put tissue on the top of each hole in the injector and the 3 drenched with gazoline leap out, however the 4th stays shut. 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 without click here success. The car is able to start if the G28 is not plugged in and it runs perfectly when it is plugged in however it has intermittent misfire issues at higher RPM. The replacement key for audi a3 coolant sensor (G62) even if it is not plugged in, shows temperatures of -49c. Also i noticed that the oil pressure gauge in the cockpit shows 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. But i am get more info afraid I might have missed something. If anyone has suggestions, please share them! TIA!
3. Fuel Pump
The fuel pump of the g28 gets a signal from the RPM sensor. The GM-style transmitter 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 salvage yard or in a local parts store. It is easy to test them - just switch your DMM into resistance mode and determine the distance between pins 1 and 2 (with the bump on the connector's edge facing up). They should be infinite ohms.
4. ECU
Our 20vt turbo (3B AAN, ABY and ADU) engines have an ECU that has to know the position and speed of the crankshaft to make decisions regarding timing of the fuel injector, for example. It uses a Crank Position Sensor G4 and an Engine Speed Sensor G28 to achieve this. If you are experiencing issues with either one of these, the diagnostic scanner will show codes that could lead to the engine shutting down.
The signs of a malfunctioning G28 sensor include an inaccurate gearbox rev counter, gears shifting quicker than normal, and/or a misfire when you are in gear. If you are experiencing any of these issues, it is likely your sensor is deteriorating and requires replacement. The good news is that they are quite affordable and easily accessible, especially when you're looking at an Bosch unit which is what ours are. Alternatively, the GM version of this unit is also a good option.
5. Tachometer
A malfunctioning engine sensor can cause a number of problems in your vehicle. It's a crucial component 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 of the car to be audi spare key replacement affected.
The G5 engine sensor is located near the edge of the transmission, just above the flywheel ring. It transmits an electrical signal through a gray wire to the ECU pin T55/49. The ECU uses this signal to regulate 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 examining the continuity of the sensor to check here the tachometer. Additionally, 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 and pin T26a/12. You should see an average resistance of 1000 ohms in these areas. This is a common feature across the Audi 80-100-200-RS2 model, ranging from the 1985 MC up to the 1997 UrS An and 1995 RS2 Du So, you may find good ones in wrecking yards.