Audi G28: 10 Things I d Loved To Know Earlier

How to Replace an spare audi key G28 Engine Speed Sensor

In this video Charles the Humble Mechanic shows how to replace the G28 engine speed sensor. This sensor is located at the top of the transmission just above the flywheel ring gear. It transmits a signal to the ECU through a grey wire T55/49, then to the tachometer located on the instrument cluster.

1. Engine Speed Sensor

The grey wire is located on the outside of the transmission, above the flywheel ring. The sensor transmits a signal via the grey wire to pin T55/49. The ECU then utilizes this information to regulate fuel, timig and boost. It also sends an indication to the G5 Tachometer in instrument cluster.

The sensor is used to link with 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 in the right way.

If this sensor fails when it fails, the ECU will display a P00160 error code. This indicates that the Crank Shaft is not in alignment with the Intake Camshaft. It could also be a sign of the possibility of a chain stretch or jumped chain link in the upper chain. However the code will not be displayed on its own without additional information from other sensors (G4 and G40).

It's a bit tricky to test because there are several pins on the connector, and they all have different functions. The best way to do it is to measure the resistance between the ECU and the sensor. It should read about 1000 ohms when it is at full operation. Check for signs of coolant or oil in the connector bay if you have issues with this part.

2. Injectors

Yesterday, when i was accelerating to the fullest speed from highway paytoll, I experienced massive power loss like the engine is out of gas or injectors aren't firing any more. This morning i pull out the spark plugs. Three were drenched in gazoline, the fourth one was dry. When I start the engine with no sparks, I put a piece of tissue on top of each injector hole and the 3 that were drenched in gazoline leap out, however the 4th stays closed. I tested the ground connection of ECU pins 14,30, and 48/55. I found 0ohm. I think the issue is in another location.

I also tried to reset PID but without success. The car can start if the G28 is disconnected and runs fine when it is plugged in however it has the intermittent misfire issue 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 but the actual pressure is 0.

I'm not sure what to do, i believe that i've ruled out everything else. I'm worried that i might have missed something. Let me know should you have any suggestions! TIA!

3. Fuel Pump

The fuel pump on the g28 is activated by a signal from the RPM sensor. The GM-style transmitter is identical to the G4 and both are used in the 80 100 200, UrS and RS2 cars so you can easily find one at a junkyard or in a local parts store. It is simple to test them by putting your DMM in resistance mode and measure the resistance 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

Our 20vt turbo (3B AAN, ABY, and ADU) engines are equipped with an ECU that must be aware of the speed and position of the crankshaft in order to make decisions about timing of the fuel injector, for example. To do this, it makes use of a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If either of these go bad you will get codes on the diagnostic scanner which could cause engine shut down.

A failing G28 sensor could result in an inaccurate speed counter for the gearbox, a gearbox that shifts more quickly than normal, and/or a misfire while in the gear. It is probable that your sensor is failing and needs to be replaced if you notice any of these signs. The good news is that they are very cheap and readily available, especially in the case of a Bosch unit which is what we have. You can also choose the GM version of this part is also a good option.

5. Tachometer

A damaged engine sensor could cause a number of problems in your car. It's an essential component of the audi smart key replacement replacement key fob - trackbookmark.com,'s transmission because it communicates to the ECU about how the car's crankshaft is rotating. This sensor can cause the transmission to malfunction and audi q5 Key other components in the car to be affected.

The G5 engine sensor is located near the edge of the transmission, just above the flywheel ring. It transmits a signal via gray wire to ECU pin T55/49. The ECU is then able to process this signal to control fuel, timig, and boost as well as transmitting it to the G5 tachometer in the instrument cluster. You can test for sensor failure by checking continuity from the sensor to the tachometer. Additionally, you can verify continuity between pin T55/49 of the ECU and pin T6a/1 of the instrument cluster (trace [79trace [79]), and between pin T6a/1 as well as pin T26a/12. You should observe approximately 1000 ohms of resistance between those points. This is a common feature across the audi key fob not working 80-100-200-RS2 model, ranging beginning with the 1985 MC and up to the 1997 UrS AN and 1995 RS2 Du, so you might find some good ones in wrecking yards.