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 near the transmission's edge just above the flywheel gear. It transmits a signal to the ECU via a grey wire (T55/49), then to the tachometer within 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 signals to ECU pin T55/49 through a grey wire. The ECU then uses this information to control the flow of fuel, timig and boost. It also sends signals to the G5 Tachometer located in the instrument cluster.
The sensor is used to correlate with the G40 Camshaft position Sensor. The ecu has to be aware of when the crankshaft has reached TDC and also the location of the camshaft in order to activate the spark and injectors.
If this sensor fails when it fails, the ECU will display a P00160 error code. This means 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 jumped chain link in the upper timing chain. However, the code won't appear on its own, without additional information from other sensors (G4 and G40).
Testing can be a bit difficult since there are two connector pins, and they serve different purposes but the most effective method to test it is to measure the resistance between the sensor and the ECU. When the sensor is operational, it should be reading about 1000 ohms. Check for signs of coolant, or oil in the connector bay if you are experiencing problems with this part.
2. Injectors
Yesterday, as i was accelerating off the highway paytoll at full speed, i noticed a huge drop in power. It was like the engine had run out of gas. Or, my injectors weren't firing. I pulled out the spark plugs this morning, 3 were soaked in gasoline, and the fourth was unclean. I placed a tissue over each injector hole, and when i start the engine with no sparks, the three that have gazoline pop right out. The 4th one remains 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 elsewhere.
I also tried to reset the PID without success. The car is able to start if the G28 is unplugged and runs fine when it is connected however it has the intermittent misfire issue at higher audi spare key replacement RPM. The coolant sensor (G62) even when unplugged, still shows a temperature of -49c. I also noticed that the oil gauge in the cockpit shows 2 bar but the actual pressure is 0.
I'm not sure what to do, but i feel i have pretty much eliminated everything else. But i'm worried that I may have missed something. Let me know if you have any ideas! TIA!
3. Fuel Pump
The fuel pump in the g28 receives signals from the RPM sensor. The GM-style transmitter is identical to the G4 sender, and both operate on the 80,100,200, UrS, and RS2 vehicles. You can easily find a spare in a wrecking shop or a parts store. It is simple to test them by putting your DMM in resistance mode and measure between pins 1 (with the bump on the connector end up) and 2 (2nd from the left on the black end of the connector). They must be infinite ohms.
4. ECU
The ECU in our 20vt turbo (3B AAN ABY) engines must be aware of the speed and position of the crankshaft to make decisions regarding timing of the fuel injector, etc. It makes use of a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If you are experiencing issues with either of these, the diagnostic scanner will display codes that could lead to an engine shutdown.
A failing G28 sensor could cause an inaccurate speed counter for your gearbox and a gearbox which shifts more quickly than normal, and/or a misfire in gear. It is possible that the sensor is failing and needs to be replaced if you experience any of these signs. The good thing is that they are quite click here affordable and readily available, especially if you're looking at an Bosch unit which is what ours are. Alternatively, GM's version of this part is a good option.
5. Tachometer
A failing engine sensor could cause a variety of issues in your vehicle. It's a vital component of the Audi's transmission since it relays information to the ECU about how fast or slow the car's crankshaft is turning. This sensor could cause the transmission to fail and other car components to be affected.
The G5 engine speed sensor is situated on the outside of the transmission just above the flywheel ring gear. It sends a signal to the ECU at pin T55/49 via an uncolored wire. The ECU then processes the signal to control fuel, timig and boost and then sends it on to the G5 tachometer in the instrument cluster. You can test the sensor for here any failure by checking the continuity between it and the tachometer. You can also check continuity between ECU pin T55/49 and the instrument cluster connection via pin T6a/1 (trace [79trace [79]) as well audi replacement car keys as between T6a/1, and the instrument cluster pin T26a/12. You should detect the resistance to be around 1000 ohms between these two points. This is a common component across the Audi 80, 100, 200, UrS and RS2 range audi car key replacement from 1985 MC through the 1997 UrS AAN and 1995 RS2 ADU, so the best parts could be found in wrecking yards.