25 Surprising Facts About Audi G28
25 Surprising Facts About Audi G28
Blog Article
How to Replace an Audi G28 Engine Speed Sensor
In this video Charles the Humble Mechanic shows how to replace the G28 engine speed sensor. The sensor is located on the outside of the transmission over the flywheel gear. It transmits a signal to the ECU via the grey wire (T55/49), then to the tachometer located in the instrument cluster.
1. Engine Speed Sensor
Located on the edge of the transmission just above the flywheel ring gear the G28 Engine Speed Sensor sends a signal to ECU pin T55/49 through a grey wire. The ECU then uses this information to control the boost, fuel, and timig. It also sends signals 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 show the P00160 error, which means the Crank Shaft and Intake Camshaft aren't in sync and possibly indicating chain stretch or a jumped link on the upper chain of timing. However, the code won't appear on its own without additional information from other sensors (G4 and G40).
Testing can be a bit difficult as there are two different connector pins and they have different functions however the best way to test it is to measure the resistance between the sensor and the ECU. It should read approximately 1000 ohms when it is in full operation. If you're experiencing issues with this part, check for signs of oil or coolant in the connector bay.
2. Injectors
Yesterday, while accelerating from the highway paytoll at maximum speed, i noticed a huge drop in power. It was like the engine had run out of gas. Or, my injectors were not firing. This morning i pull out the spark plugs, three were drenched in gazoline, the fourth was dry. When I start the engine without sparks i put tissue on top of each injector hole, the 3 drenched with gazoline pop out, but the 4th stay closed. I tested the ground connection of ECU pins 14,30, and 48/55. I found zero ohm. Therefore, i think the issue is elsewhere.
I also tried to reset PID but without success. The car will start when the G28 is not plugged in and it runs perfectly when it is plugged in but it still has intermittent misfire issues at higher RPM. The coolant sensor (G62) even if it is not plugged in, shows temperatures of -49c. Also i noticed that the gauge for oil pressure in the cockpit is showing 2 bar while the actual pressure is 0.0 when I crank up 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 suggestions, please let me know! TIA!
3. Fuel Pump
The fuel pump of the g28 gets a signal from the RPM sensor. The GM-style transmitter is the same as the G4 and both are used in the 80 100, 200, UrS and RS2 cars which is why you can easily locate one at a wrecking yard or in a local parts store. It is simple to test them - simply switch your DMM into resistance mode and test 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 needs to know the speed and position of the crankshaft to make a decision about fuel injector timing etc. It makes use of a Crank Position Sensor G4 and an Engine Speed Sensor G28 to achieve this. If you are experiencing issues with either of these, the diagnostic scanner will display codes that could lead to the engine shutting down.
The signs of a failed G28 sensor are an inaccurate gearbox rev counter the gears are shifting faster than normal, and/or a misfire when you are in gear. If you experience any of these issues, check here it is likely that your sensor is deteriorating and needs replacing. The good news is they are very affordable and easily accessible, especially if you're looking at the Bosch unit which is what ours are. You can also choose the GM version of this unit is also a great option.
5. Tachometer
A malfunctioning engine speed sensor could be the reason behind a slew of issues with your vehicle. It's click here an essential component more info of the Audi's transmission since it relays information to the ECU about how the car's crankshaft is rotating. When this sensor fails, it could cause problems for the transmission, as well as the other car's get more info components.
The G5 engine sensor is located at the outskirts of the transmission, just above the flywheel ring. It transmits a signal via gray wire to ECU pin T55/49. The ECU utilizes this signal to regulate the amount of fuel and boost, and also timig. It also sends it to the G5 Tachometer located in the instrument cluster. You can determine if the sensor is in failure by checking continuity from the sensor to the tachometer. You can also check continuity between pin T55/49 of the ECU and pin here T6a/1 of the instrument cluster (trace [79]) and between pin T6a/1 and pin T26a/12. There should be the resistance to be around 1000 ohms between these points. This is the same across the Audi 80-100-200-RS2 range, from the 1985 MC all the way up to the 1997 UrS An and 1995 RS2 Du So, you may find them in wrecking yards.