"The Ultimate Cheat Sheet" For Audi G28
"The Ultimate Cheat Sheet" For Audi G28
Blog Article
How to Replace an Audi G28 Engine Speed Sensor
Charles the Humble Technician shows how to replace the G28 Engine Speed Sensor. The sensor is situated at the top of the transmission above the flywheel ring gear. It transmits a signal to the ECU via the grey wire (T55/49), then to the tachometer within the instrument cluster.
1. Engine Speed Sensor
The grey wire is situated at the edges of the transmission, just above the flywheel ring. The sensor transmits a signal via the grey wire to pin T55/49. The ECU utilizes this information to regulate the amount of fuel and boost. It also sends an alert to the G5 Tachometer located in the instrument cluster.
The sensor is used as a reference to correlate 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 activate spark and injectors according to the situation.
If this sensor fails, the ECU will display an error code P00160. This means that the Crank Shaft is not in sync with the Intake Camshaft. It could also be a sign of a chain stretch or a jumpy chain link in the upper chain. However, the code won't appear on its own without additional information from other sensors (G4 and G40).
It can be a bit difficult to test because there are several pins on the connector and they all have different functions. The best method for doing this is by measuring the resistance between the ECU and the sensor. It should read around 1000 ohms when the sensor is in full operation. If you are having problems with this component, look for evidence of coolant or oil in the connector bay.
2. Injectors
Yesterday, as i was accelerating off the highway paytoll at a high speed I noticed a massive decrease in power. It was as if the engine was running out of gas. Or, my injectors were not firing. This morning i pull out the spark plugs, 3 were drenched with gazoline the fourth was dry. When I crank the engine, there are no sparks, i place a tissue on the top of each of the injector holes and the 3 drenched with gazoline leap out, however the 4th stays shut. I tried to test the ground connections of ECU pins 14,30, and 48/55. I got 0ohm. So i assume the problem is in another place.
I also tried to reset the PID without success. The car will start when the G28 is disconnected, but it works fine check here when the G28 plugged in. However the intermittent misfire issue continues to occur at higher RPM. The coolant sensor (G62) even when it is unplugged, shows an ice temperature of -49c. I also noticed that the oil pressure gauge in the cockpit shows 2 bar, whereas the actual pressure is 0.0 if i crank up the engine.
I'm not sure what to do. I think I've ruled everything else out. I'm afraid i may have missed something. If anyone has suggestions, please chime in! TIA!
3. Fuel Pump
The fuel pump more info in the g28 is activated by a signal from the RPM sensor. The GM-style transmitter is identical to the G4 sender and works on the 80,100,200, UrS, and RS2 vehicles. You can easily find an extra in a wrecking shop or parts store. It is simple to test them - simply put read more your DMM into resistance mode and test the distance between pins 1 and 2 (with the bump at the connector end facing upwards). 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 determine fuel injector timing, etc. It uses a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If either of these go badly, you will see codes on the diagnostic scanner which can cause the engine to shut down.
Some of the signs of a failed G28 sensor include here an inaccurate gearbox rev counter, gears shifting quicker than normal and/or a misfire when in gear. If you are experiencing any of these issues, it is most likely that your sensor is deteriorating and should be replaced. They are cheap and easy-to-find, especially when they're an Bosch unit like ours. Alternatively, the GM version of this component is also a good choice.
5. Tachometer
A malfunctioning engine speed sensor could be the cause of many problems in your vehicle. It's a vital component of your Audi's transmission, since it relays information to the ECU about how fast or slow the car's crankshaft is rotating. If the sensor fails, it can cause problems for the transmission and the other car's components.
The G5 engine speed sensor is located on the outside of the transmission above the flywheel ring gear. It transmits a signal to the ECU at pin T55/49, via a grey wire. The ECU uses this signal to regulate fuel and boost, and also to timigrate. It also relays it to the G5 Tachometer in instrument cluster. You can check the sensor for failure by checking continuity between it and the tachometer, between ECU pin T55/49 and the instrument cluster connection via pin T6a/1 (trace [79]) and between pin T6a/1 and the instrument cluster pin T26a/12. There should be the resistance to be around 1000 ohms between these points. This more info is a common 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 parts could be found in wrecking yards.