Its The Complete Cheat Sheet On Audi G28

How to Replace an Audi G28 Engine Speed Sensor
In this video Charles the Humble Mechanic shows how to replace the G28 engine speed sensor. The sensor is situated on the edge of the transmission just above the flywheel ring gear. It sends a signal to the ECU via the grey wire (T55/49) and then to the tachometer located 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 uses this information to regulate boost and fuel. It also sends an alert to the G5 Tachometer within the instrument cluster.
The sensor serves as a reference point to connect with the G40 Camshaft Position Sensor. The ecu has to be aware of when the crankshaft has reached TDC and also the position of the camshaft, to trigger 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, possibly indicating the chain stretching or a jump link on the upper timing chain. The code won't appear without the additional information provided by other sensors (G4 or G40).
It can be a bit difficult to test as there are different pins on the connector and each one has different functions. The best method for doing this is by measuring the resistance between the ECU and the sensor. If the sensor is operational, it should be reading around 1000 ohms. If mouse click the following web page having issues with this sensor, 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 an abrupt drop in power as if the engine was running out of gas or the injectors aren't firing anymore. I took out the spark plugs this morning and found that 3 were drenched in gasoline and the 4th was dry. When I crank the engine, there are no sparks i put tissue on the top of each of the injector holes, the 3 drenched with gazoline pop out, but the 4th one stays closed. I tested the ground connection of ECU pins 14,30, and 48/55. I got zero ohm. Therefore, i think the issue is somewhere else.
I also tried to reset PID but without success. The car will start when the G28 is unplugged, and it runs fine with the G28 plugged in. However new audi key persists at higher RPM. The coolant sensor (G62), even when it is unplugged, shows an ice temperature of -49c. I also noticed that the gauge for oil pressure in the cockpit is showing 2 bar when the actual pressure is 0.0 when I crank up the engine.
I'm not sure what to do, as i believe that i've eliminated everything else. I'm afraid i may have missed something. If anyone has any ideas please share them! TIA!
3. Fuel Pump
The fuel pump on the g28 is activated by a signal from the RPM sensor. The GM-style transmitter is identical to the G4 sender and both work on the 80,100,200, UrS, and RS2 vehicles. You can easily find the spare in a salvage shop or a parts store. It is simple to test them - just put your DMM into resistance mode and measure the distance between pins 1 and 2 (with the bump at the connector end facing up). They must be infinite Ohms.
4. ECU
The ECU of our 20vt turbo (3B AAN ABY) engines needs to be aware of the position and speed of the crankshaft to make decisions regarding timing of the fuel injector, etc. It makes use of a Crank Position Sensor G4 and an Engine Speed Sensor G28 to achieve this. If you have a problem with either of these, the diagnostic scanner will display codes that could lead to an engine shutdown.
The signs of a failing G28 sensor include an inaccurate gearbox rev counter, gears shifting quicker than normal, and/or a misfire when you are in gear. It is possible that your sensor is failing and needs to be replaced if you experience any of these signs. They're inexpensive and easy to locate, especially if they're an Bosch unit like ours. Alternately, GM's version this component is an excellent choice.
5. Tachometer
A damaged engine sensor could cause a number of problems in your car. It's a crucial component of the transmission in your Audi because it relays information to the ECU regarding how fast or slowly the engine of the car is spinning. This sensor could cause the transmission to malfunction and other components in the car to be affected.
Read the Full Write-up is located at the edge of the transmission, over the flywheel ring. It transmits signals via gray wire to ECU pin T55/49. The ECU then uses and processes this signal to regulate fuel, timig, and boost and then sends it on to the G5 Tachometer located in the instrument cluster. You can check the sensor for failure by examining the continuity between it and the tachometer. You can also check continuity between ECU pin T55/49 and the instrument cluster connection to pin T6a/1 (trace [79trace [79]) as well as between T6a/1, and the instrument cluster pin T26a/12. You should detect an average resistance of 1000 ohms between these points. This is a standard part across the Audi 80 100 200, UrS and RS2 range from 1985 MC until the 1997 UrS AAN and 1995 RS2 ADU, so the best ones might be availble in wrecking yards.