This Weeks Top Stories About Audi G28 Audi G28

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 situated near the transmission's edge, above the flywheel gear. It sends a message to the ECU through an uncolored wire T55/49, then to the tachometer in the instrument cluster.
1. Engine Speed Sensor
Located on the edge of the transmission above the flywheel ring gear G28 Engine Speed Sensor sends signals to ECU pin T55/49 via a grey wire. The ECU uses this information to control the amount of fuel and boost. It also sends an indication to the G5 tachometer in the instrument cluster.
The sensor is used as a reference for comparing with the G40 Camshaft Position Sensor. The ecu must be aware of when the crankshaft has reached TDC and also where the camshaft lies so that it can activate the spark and injectors.
If this sensor fails the ECU will show a P00160 code which means the Crank Shaft and Intake Camshaft are out of sync and could indicate chain stretch or a jumped link on the upper timing chain. The code won't show without the additional information provided by other sensors (G4 or G40).
It's a bit tricky to test as there are different pins on the connector, and each has its own functions. The best way to do it is to measure the resistance between the ECU and the sensor. If the sensor is operational, it should read around 1000 ohms. Examine for signs of coolant or oil in the connector bay if you have issues with this component.
2. Injectors
Yesterday, when i was accelerating to the fullest speed from highway paytoll, i experienced a big cut in power like the engine is out of gas or injectors aren't firing any more. Today, i pulled out the spark plugs, three were soaked with gazoline and the fourth one was dry. I put tissue over each injector hole, and when i start the engine with no sparks, the 3 with gazoline jump right out. The fourth one remains shut. I checked the ground connection on ECU pins 14/55,30/55 and 48/55 I got zero Ohm. I think the issue is elsewhere.
I also tried to reset the PID but with no luck. The car will start when the G28 is unplugged, and it is running fine with the G28 connected. However, the intermittent misfire problem continues to occur at higher RPM. The coolant sensor (G62), even if it is not plugged in, shows temperatures of -49c. I also noticed that the oil gauge in the cockpit shows 2 bar but the actual pressure is zero.
I'm not sure what to do. I believe that I've all other possibilities out. I'm worried that i might have missed something. If anyone has any ideas 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 so you can easily find one at a wrecking yard or at a parts store. It is simple to test them to do - just put your DMM in resistance mode and measure the resistance between pins 1 (with the bump on the connector's end up) and 2 (2nd from left on the black connector's end). They should be infinite Ohms.
4. ECU
The ECU in our 20vt turbo (3B AAN ABY) engines needs to be aware of the speed and position of the crankshaft to determine timing of fuel injectors, etc. It makes use of a Crank Position Sensor G4 and an Engine Speed Sensor G28 to achieve this. If you encounter a problem with either of these sensors, the diagnostic scanner will display the codes that could trigger an engine shutdown.
A failing G28 sensor can cause an inaccurate speed counter for your gearbox, a gearbox that shifts more quickly than normal, and/or an unfire when in gear. If you are experiencing any of these issues, it is likely your sensor is deteriorating and should be replaced. The good thing is that they are quite affordable and readily available particularly if you're looking at a Bosch unit which is what we have. Alternately, the GM version of this unit is also a great option.
5. Tachometer
A malfunctioning engine sensor can cause a variety of issues in your vehicle. It's a vital component of your Audi's transmission, since it relays information to the ECU about how fast or slow the vehicle's crankshaft is spinning. This sensor can cause the transmission to malfunction 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 an electrical signal through an uncolored wire to the ECU pin T55/49. The ECU uses this signal to control fuel and boost, and also to timigrate. Our Home Page transmits it to the G5 Tachometer located in the instrument cluster. You can determine if the sensor is in failure by checking continuity from the sensor to the tachometer. Additionally, you can check 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. There should be an average resistance of 1000 ohms in these areas. This is a common feature across the Audi 80-100-200-RS2 series, starting from the 1985 MC all the way up to the 1997 UrS AN and 1995 RS2 Du You may also find them in wrecking yards.