7 Small Changes You Can Make That'll Make The Difference With Your Audi G28 > 자유게시판

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 transmission's edge over the flywheel gear. It sends a signal to the ECU via a grey wire (T55/49) which is then sent to the tachometer located in the instrument cluster.

1. Engine Speed Sensor

The grey wire is located on the edge of transmission, above the flywheel ring. This sensor sends a signal via the grey wire to pin T55/49. The ECU then uses this information to control fuel, timig and boost. It also sends signals to the G5 tachometer inside the instrument cluster.

The sensor serves as a reference to correlate with the G40 Camshaft Position Sensor. The ecu must be aware when the crankshaft is TDC and where the camshaft is located so that it can activate spark and injectors in the right way.

If this sensor fails, the ECU will throw an error code P00160 which indicates that the Crank Shaft and Intake Camshaft aren't in sync and could indicate chain stretch or a jumped link on the upper timing 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 however the best method to test it is by measuring resistance between the sensor and the ECU. If the sensor is operational, it should read around 1000 ohms. If you're experiencing issues with this part, check for signs of coolant or oil in the connector bay.

2. Injectors

Yesterday accelerating full speed from highway paytoll, I experienced an abrupt drop in power like the engine is running out of gas or injectors are not firing any more. In the morning, i removed the spark plugs, three were soaked with gazoline and the 4th one was dry. When I crank the engine without sparks i put tissue on the top of each of the injector holes and the 3 drenched with gazoline leap out, however the 4th stay closed. I checked the ground connection on ECU pins 14/55,30/55 and 48/55 I got zero ohm. I assume that the problem is in another location.

I also tried to reset PID but without success. The car is able to start when the G28 is unplugged and runs fine when it is plugged in but it still is experiencing intermittent misfires at higher RPM. The temperature sensor for the coolant (G62) shows the wrong temperature value of -49c, even if I unplug it. Also i noticed that the oil pressure gauge in the cockpit is showing 2 bar while the actual pressure is 0.0 when i rev 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. 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 by the RPM sensor. The GM-style transmitter is similar to the G4 sender, and both operate on the 80,100,200, UrS, and RS2 vehicles. You can easily locate a spare in a wrecking shop or a parts store. It is easy to test them - just put your DMM into resistance mode and Audi Q5 Key test the distance between pins 1 and 2 (with the bump at the connector's end facing up). They must be infinite Ohms.

4. ECU

The ECU in our 20vt turbo (3B AAN ABY ADU) engines must be aware of the position and speed of the crankshaft in order to make a decision about fuel injector timing, etc. It utilizes a Crank Position Sensor G4 and an Engine Speed Sensor G28 to achieve this. If either of these sensors go bad you will get codes on the diagnostic scanner which could cause engine shut down.

A malfunctioning G28 sensor could cause an inaccurate speed counter for the gearbox and a gearbox which shifts faster than normal, and/or a misfire while in the gear. If you experience any of these issues, it is most likely that your sensor is deteriorating and needs replacing. They're cheap and easy to find, especially in the case of an Bosch sensor like ours. Alternatively, GM's version of this part is an option.

5. Tachometer

A failing engine speed sensor could be the reason behind a slew of problems in your vehicle. It's an essential component of the transmission in your audi key fob not working since it sends information to the ECU on how fast or slowly the engine is turning. When this sensor fails, it will affect the performance of the transmission and the other car's components.

The G5 engine speed sensor is situated on the edge of the transmission, above the flywheel ring gear and transmits a signal to the ECU at pin T55/49, via a grey wire. The ECU then uses and processes this signal to control fuel, timig and boost, and also sends it on to the G5 Tachometer located in the instrument cluster. You can determine if the sensor is in failure by examining the continuity from the sensor to the tachometer. Additionally, you can verify continuity between pin T55/49 of the ECU and pin T6a/1 of the instrument cluster (trace [79]) and between pin T6a/1 and pin T26a/12. You should see an average resistance of 1000 ohms between these two points. This is the same across the Audi Q5 Key 80-100-200-RS2 range, from the 1985 MC all the way up to the 1997 UrS An and 1995 RS2 DU You may also find good ones in wrecking yards.