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 on the edge of the transmission, above the flywheel ring gear. It sends a message to the ECU via a grey wire T55/49, then to the tachometer in the instrument cluster.
1. Engine Speed Sensor
It is located on the outside of the transmission, above the flywheel ring gear G28 Engine Speed Sensor sends an electrical signal to ECU pin T55/49 via a grey wire. The ECU then utilizes this information to regulate the boost, fuel, and timig. It also sends an indication to the G5 tachometer in the instrument cluster.
The sensor is used to connect with the G40 Camshaft position Sensor. The ecu must know when the crankshaft is TDC and where the camshaft is located so that it can trigger spark and injectors in the right way.
If this sensor fails to function, the ECU will display a P00160 error code. This means that the Crank Shaft is not in line with the Intake Camshaft. It could also be a sign of an issue with the chain or a jump in the chain link of the upper chain. The code won't appear without the additional information provided by other sensors (G4 or G40).
Testing is a bit challenging because there are two connector pins and they perform different functions but the best method of testing it is to measure the resistance between the sensor and the ECU. If the sensor is functional, it should read around 1000 ohms. If you're experiencing issues with this part, check for signs of oil or coolant in the connector bay.
2. Injectors
Yesterday, when i was accelerating to the fullest speed from highway paytoll, i experienced a big cut in power as if the engine was running out of gas or injectors aren't firing anymore. This morning i pull out the spark plugs, 3 were drenched in gazoline, the fourth 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 stays shut. I checked the ground connection on ECU pins 14/55,30/55 and 48/55 I get zero ohm. Therefore, i think the issue is elsewhere.
I also tried to reset the PID with no success. The car can start if the G28 is disconnected and is running 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 temp value that is audi car keys replacement -49c even after unplugging it. Also, i noticed that the oil pressure gauge in the cockpit shows 2 bar when the actual pressure is 0.0 when i rev the engine.
I'm not sure what to do. I think I've ruled everything else out. I'm concerned that i may have missed something. If anyone has any genuine audi key replacement ideas please chime in! TIA!
3. Fuel Pump
The fuel pump of the g28 receives signals 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 which is why you can easily locate one at a wrecking yard or from a parts store. It is simple to test them - just switch your DMM into resistance mode and measure the distance between pins 1 and 2 (with the bump on the connector's edge facing up). They should be infinite Ohms.
4. ECU
Our 20vt turbo (3B, AAN, ABY and ADU) engines are equipped with an ECU that must know the speed and position of the crankshaft in order to make decisions about timing of the fuel injectors, etc. To accomplish this, it uses 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 which can lead to engine shutdown.
Some of the signs of a failed G28 sensor are an inaccurate gearbox rev counter and gears that shift faster than normal and/or a misfire when you're in gear. It get more info is possible that your sensor is failing and requires to be replaced if you encounter any of these symptoms. They are cheap and easy-to-find particularly in the case of a Bosch model like ours. If you prefer, GM's version of this part would be an excellent choice.
5. Tachometer
A malfunctioning engine sensor can cause a myriad of issues in your car. It's an essential component of the transmission of your Audi because it relays information to the ECU on how fast or slowly the engine is turning. If this sensor fails, it could disrupt the performance of the transmission and the rest of the car's components.
The G5 engine speed sensor is located at the outside of the transmission above the flywheel ring gear. It sends a signal to the ECU at pin T55/49 through a grey wire. The ECU is then able to process the signal to control fuel, timig, and boost, and also transmitting it to the G5 audi a4 key replacement Tachometer located in the instrument cluster. You can check for sensor failure by examining the continuity from the sensor to the replacement audi car key tachometer. Also, you can examine the continuity between pins T55/49 of the ECU and pin T6a/1 of the instrument cluster (trace [79trace [79]), and between pin T6a/1 as well as pin T26a/12. It should show around 1000 ohms of resistance between these two points. This is a standard part that is found across the Audi 80, 100, 200, UrS and RS2 range from 1985 MC to the 1997 UrS AAN and 1995 RS2 ADU, so the best ones might be availble in wrecking yards.