How to Replace an Audi G28 Engine Speed Sensor
Charles the Humble Technician shows you how to replace the G28 Engine Speed Sensor. The sensor is situated on the edge of the transmission just above the flywheel ring gear. It sends a signal to the ECU via an uncolored 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 G28 Engine Speed Sensor sends signals to ECU pin T55/49 using the grey wire. The ECU then uses this information to control the boost, fuel, and timig. audi advanced key sends an indication to the G5 tachometer in the instrument cluster.
The sensor is used to correlate the G40 Camshaft position Sensor. The ecu must know when the crankshaft is TDC and where the camshaft is so it can trigger spark and injectors according to the situation.
If this sensor fails the ECU will throw 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 will not appear on its own without additional information from other sensors (G4 and G40).
It is a little tricky to test because there are different pins on the connector, and each has its own functions. The best method for doing this is to measure the resistance between the ECU and the sensor. It should read approximately 1000 ohms when it is at full operation. Check for evidence of coolant or oil in the connector bay if you are experiencing problems with this part.
2. Injectors
Yesterday, when i was accelerating to the fullest speed from highway paytoll, i experienced massive power loss as if the engine was running out of gas or the injectors aren't firing any more. In the morning, i removed the spark plugs, 3 were drenched in gazoline, the fourth was dry. When i crank the engine without sparks, I put a piece of tissue on top of each injector hole and the 3 that were drenched in gazoline jump out but the 4th stays closed. I inspected the ground connection on ECU pins 14/55,30/55 and 48/55 I get zero ohm. I'm assuming the issue is elsewhere.
I also tried to reset the PID without success. The car will start if the G28 is not plugged in and runs fine when it is connected but it still has the intermittent misfire issue at higher RPM. The temperature sensor for the coolant (G62) shows the wrong temperature of -49c, even if I unplug it. I also noticed that the oil gauge in the cockpit shows 2 bar while the actual pressure is 0.
I'm not sure what to do. I feel like i've pretty much eliminated everything else. I'm worried that i might have missed something. If anyone has any suggestions, please share them! TIA!
3. Fuel Pump
The fuel pump of the g28 receives a signal 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 parts store. Test them out by putting your DMM in resistance mode and take measurements between pins 1 (with the bump on the connector's end up) and 2 (2nd from the left on the black connector's side). They must be infinite Ohms.
4. ECU
The ECU of our 20vt turbo (3B AAN ABY ADU) engines needs to know both the speed and position of the crankshaft in order to make a decision about timing of fuel injectors, etc. It utilizes 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 cause an engine shut down.
audi key programming near me failing G28 sensor could result in an inaccurate speed counter for the gearbox, a gearbox that shifts faster than normal, or a misfire in gear. It is possible that your sensor is failing and needs to be replaced if you encounter any of these symptoms. audi key programming near me and easy to locate particularly if they're a Bosch model like ours. Alternatively, the GM version of this component is also a great option.
5. Tachometer
A failing engine speed sensor could be the reason behind numerous issues 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 vehicle's crankshaft is turning. This sensor can cause the transmission to fail and other components in the car to be affected.
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 via an uncolored wire. The ECU is then able to process this signal to control fuel, timig and boost and then sends it on to the G5 tachometer inside the instrument cluster. You can check the sensor for failure by examining the continuity between it and the tachometer, between the ECU pin T55/49 and the instrument cluster connection via pin T6a/1 (trace [79trace [79]) as well as between T6a/1, and the instrument cluster pin T26a/12. You should detect the resistance to be around 1000 ohms between these points. This part is common across the Audi 80-100-200-RS2 range, beginning with the 1985 MC and up to the 1997 UrS An and 1995 RS2 Du, so you might find good ones in wrecking yards.
