How to Replace an Audi G28 Engine Speed Sensor
In this video, Charles the humble mechanic demonstrates how to replace the G28 engine speed sensor. The sensor is located at the edge of transmission just above the flywheel gear. It transmits a signal the ECU via the grey wire (T55/49) and then to the tachometer located in the instrument cluster.
1. Engine Speed Sensor
The sensor is located at the edge of the transmission just above the flywheel ring gear G28 Engine Speed Sensor sends a signal to ECU pin T55/49 through an uncolored wire. The ECU then utilizes this information to regulate fuel, timig and boost. It also sends a signal to the G5 tachometer inside the instrument cluster.
The sensor is used to correlate the G40 Camshaft position Sensor. The ecu must be aware of when the crankshaft has reached TDC, and the location of the camshaft in order to activate the spark and injectors.
If this sensor fails, the ECU will display a P00160 error message. This indicates that the Crank Shaft is out of sync with the Intake Camshaft. It could also be a sign of an issue with the chain or a jumpy chain link in the upper chain. However, the error code won't appear on its own, without additional information from other sensors (G4 and G40).
It's a bit tricky to test because there are different pins on the connector, and each one has different functions. The most effective method to test it is to measure the resistance between the ECU and the sensor. It should read about 1000 ohms when the sensor is operating at its maximum. Look for signs of coolant or oil in the connector bay if you have problems with this part.
2. Injectors
Yesterday, while accelerating from the highway paytoll at maximum speed, i noticed a huge decrease in power. It was as if the engine was running out of gas. Or my injectors weren't firing. In the morning, i removed the spark plugs. Three were soaked with gazoline and the fourth was dry. When I crank the engine, there are no sparks, i place a tissue on the top of each hole in the injector, the 3 drenched with gazoline jump out but the 4th stay shut. 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 the PID but without success. The car can start if the G28 is not plugged in and runs fine when it is connected, but still has intermittent misfire issues at higher RPM. The temperature sensor for the coolant (G62) shows the wrong temperature value of that is -49c even after unplugging it. I also noticed that the gauge for oil pressure in the cockpit shows 2 bar while the actual pressure is 0.0 if i crank up the engine.
I'm not sure what to do. I believe that I've all other possibilities out. However, i'm afraid that i might 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 sent by the RPM sensor. The GM-style transmitter is the same as 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 at a parts store. Test them out by putting your DMM in resistance mode and take measurements between pins 1 (with the bump on the connector's end up) and 2 (2nd from left on the black connector's end). They must be infinite ohms.
4. ECU
Our 20vt turbo (3B AAN, ABY, and ADU) engines are equipped with an ECU that must be aware of the speed and position of the crankshaft in order to make a audi advanced key decision about fuel injector timing etc. To accomplish this, it makes use of a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If either of these goes wrong, you will receive codes on the diagnostic scanner that can cause the engine to shut down.
A damaged G28 sensor could cause an inaccurate speed counter for your gearbox and a gearbox which shifts faster than normal, or a misfire while in gear. If you experience any of these issues it is most likely that your sensor is deteriorating and should be lost audi keys replaced. The good news is that they are very affordable and easily accessible particularly in the case of a Bosch unit like ours. Alternatively, GM's version of this component is an excellent choice.
5. Tachometer
A replacement audi car key malfunctioning engine sensor can cause a number of problems within your vehicle. It's an essential component of the transmission in your more info Audi since it sends information to the ECU about how fast or slowly the engine is spinning. If this sensor fails, it will disrupt the performance of the transmission and the rest of the car's components.
The G5 engine speed sensor is located on the outside of the transmission, above the flywheel ring gear. It sends a signal directly to the ECU at pin T55/49 via a grey wire. The ECU then processes this signal to control the flow of fuel, timig and boost and then sends it on to the G5 click here Tachometer located in the instrument cluster. You can check for sensor failure by checking continuity from the sensor to the tachometer. Additionally, you can 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 and pin T26a/12. You should detect an average resistance of 1000 ohms between these points. This is a common feature across the Audi 80-100-200-RS2 range, beginning with the 1985 MC and up to the 1997 UrS AN and 1995 RS2 DU So, you may find good ones in wrecking yards.