What The Heck Is Audi G28?
What The Heck Is Audi G28?
Blog Article
How to Replace an Audi G28 Engine Speed Sensor
Charles the Humble Technician teaches you how to replace the G28 Engine Speed Sensor. This sensor is located at the edge of transmission over the flywheel gear. It sends a message to the ECU through the grey wire T55/49 and then to the tachometer 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 transmits an electrical signal through the grey wire to pin T55/49. The ECU uses this information to regulate the amount of fuel and boost. It also sends an indication to the G5 tachometer in the instrument cluster.
The sensor is used to connect the G40 Camshaft position Sensor. The ecu must know when the crankshaft reached TDC and also the location of the camshaft so that it can activate the spark and injectors.
If this sensor fails, the ECU will display an error code P00160. This indicates that the Crank Shaft is out of alignment 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 of timing. The code won't appear without the additional information supplied by other sensors (G4 or G40).
Testing is a bit tricky since there are two pins for the connector and they have different functions but the best way to test it is by measuring resistance between the sensor and the ECU. It should read around 1000 ohms when the sensor is in full operation. Look for signs of coolant, or oil in the connector bay if you are experiencing issues with this part.
2. Injectors
Yesterday, as i was accelerating off the highway paytoll at full speed, i noticed a huge decrease in power. It was like the engine was running out of gas. Or my injectors weren't firing. In the morning, i removed the spark plugs. Three were drenched in gazoline, the 4th one was dry. When i crank the engine without sparks i put tissue on top of each injector hole and the 3 drenched with gazoline pop out, but the 4th one stays shut. I inspected the ground connection on ECU pins 14/55,30/55 and 48/55 I get zero Ohm. I'm assuming that the issue is in another location.
I also tried to reset the PID without success. The car will start when the G28 is disconnected, but it works fine when the G28 connected. However the intermittent misfire issue continues to occur read more at higher RPM. The temperature sensor for the coolant (G62) shows the wrong temp value -49c, even if I unplug it. I also noticed that the oil gauge in the cockpit shows 2 bar when the actual pressure is 0.
I'm not certain what to do, as i believe that i've ruled out 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 here GM-style transmitter functions similarly to the G4 sender and works on the 80,100,200, UrS, and RS2 vehicles. You can easily find a spare in a wrecking shop or parts store. It is easy to test them - simply put your DMM into resistance mode and determine the distance between pins 1 and 2 (with the bump at the connector's end facing upwards). They must be infinite Ohms.
4. ECU
Our 20vt turbo (3B AAN, ABY, and ADU) engines have an ECU that must know the speed and position of the crankshaft in order to make decisions about timing of the fuel injectors, etc. It makes use of a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If either of these goes wrong, you will receive codes on the diagnostic scanner that could cause engine shut down.
Some of the signs of a failing G28 sensor are an inaccurate gearbox rev counter the gears are shifting faster than normal, and/or a misfire when you're in gear. If you have any of these issues, it is likely that your sensor is going bad and needs replacing. They're cheap and easy to find especially if they're an Bosch sensor like ours. Alternately, GM's version this component is an option.
5. Tachometer
A failing engine sensor could cause a variety of issues within your vehicle. It is a crucial part of your Audi's transmission, as it sends information to the ECU about how fast or slow the car's crankshaft is spinning. If this sensor fails, it could affect the performance of the click here transmission as well as the other car's components.
The G5 engine speed sensor is located at the edge of the transmission above the flywheel ring gear and sends a signal directly to the ECU at pin T55/49 through a grey wire. The ECU is then able to process the signal to control the flow of fuel, timig and boost, and also sends it on to the G5 Tachometer located in the instrument cluster. You can test for sensor failure by checking continuity from the sensor to the tachometer. replacement car key audi 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 observe around 1000 more info ohms of resistance between those two pins. This is the same across the Audi 80-100-200-RS2 range, beginning with the 1985 MC and up to the 1997 UrS AN and 1995 RS2 Du You may also find them in wrecking yards.