This Week's Most Popular Stories Concerning Audi G28
This Week's Most Popular Stories Concerning Audi G28
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How to Replace an Audi G28 Engine Speed Sensor
Charles the Humble Technician teaches how to replace the G28 Engine Speed Sensor. This sensor is located at the top of the transmission, above the flywheel ring gear. It transmits a signal the ECU via an uncolored wire (T55/49) which is then sent to the tachometer within the instrument cluster.
1. Engine Speed Sensor
It is located on the outside of the transmission above the flywheel ring gear the G28 Engine Speed Sensor sends a signal to ECU pin T55/49 via the grey wire. The ECU uses this information to regulate the amount of fuel and boost. It also sends an indicator to the G5 Tachometer within the instrument cluster.
The sensor is used to connect with the G40 Camshaft position Sensor. The ecu must know when the crankshaft reached TDC and also where the camshaft lies in order to activate the spark and injectors.
If this sensor fails, the ECU will throw the P00160 error, which means the Crank Shaft and Intake Camshaft are not in sync and possibly indicating the chain is stretched or a jump link on the upper timing chain. The code won't appear without the additional information supplied by other sensors (G4 or G40).
It's a bit tricky to test as there are various connector pins, and each one has different functions. The best method for doing this is by measuring the resistance between the ECU and the sensor. When the sensor is operational, it should read about 1000 ohms. If you're experiencing issues with this sensor, look for evidence of oil or coolant in the connector bay.
2. Injectors
Yesterday accelerating full speed from highway paytoll, I experienced a big cut in power like the engine is running out of gas or injectors aren't firing any more. I took out the spark plugs this morning, 3 were soaked in gasoline, and the 4th was dry. I put tissue over each injector hole, and when i start the engine with no sparks, the three with gazoline jump out. The 4th one stays shut. I tried to test the ground connections of ECU pins 14,30 and 48/55. I found zero ohm. Therefore, i think the issue is somewhere else.
I also tried to reset PID without success. The car is able to start when the G28 is unplugged and runs fine when read more it is connected, check here but still has the intermittent misfire issue at higher RPM. The temperature sensor for coolant (G62) shows the wrong temp value -49c even when i unplug it. I also noticed that the oil gauge in the cockpit shows 2 bars while the actual pressure is 0.
I'm not sure what to do. I believe that I've all other possibilities out. But i am afraid I might have missed something. Please let me know If you have any suggestions! TIA!
3. Fuel Pump
The fuel pump in the g28 can be activated by a signal sent from the RPM sensor. The GM-style sender is identical to the G4 and they both work in the 80, 100, 200, UrS and RS2 cars so you can easily find one at a wrecking yard or in a local parts store. Test them out to do - just put your DMM in resistance mode and take measurements between pins 1 (with the bump on the connector's end up) and 2 (2nd from the left on the black connector's side). They must be infinite Ohms.
4. ECU
Our 20vt turbo (3B AAN, ABY and ADU) engines have an ECU that needs to be aware of the speed and position of the crankshaft to make a decision about timing of the fuel injectors, etc. 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 the engine shutting down.
A failing G28 sensor could cause an inaccurate speed counter for your gearbox and a gearbox which shifts more quickly than normal, or an unfire when in gear. If you experience any of these problems, it is likely that your sensor is failing and requires replacement. The good thing is that they are very affordable and easily accessible, especially if you're looking at a Bosch unit like ours. Alternatively, the GM version of this unit is also a good option.
5. Tachometer
A malfunctioning engine sensor can cause a number of problems within your vehicle. It's an essential component of your Audi's transmission, as it sends information to the ECU about how check here fast or slow the vehicle's crankshaft is turning. If this sensor fails, it can cause problems for the transmission and the other car's components.
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 website also relays it to the G5 Tachometer in instrument cluster. You can test for sensor failure by checking continuity from the sensor to the tachometer. You can also examine the continuity between pins T55/49 of the ECU and pin T6a/1 of the instrument cluster (trace [79]), and between pin T6a/1 as well get more info as pin T26a/12. You should observe around 1000 ohms of resistance between these two 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 could be available in wrecking yards.