7 Little Changes That Will Make An Enormous Difference To Your Audi G28 > 자유게시판

How to Replace an replacement audi a3 key G28 Engine Speed Sensor

Charles the Humble Technician shows how to replace the G28 Engine Speed Sensor. The sensor is located on the edge of the transmission just above the flywheel ring gear. It transmits a signal to the ECU via a grey wire T55/49, then to the tachometer located on the instrument cluster.

1. Engine Speed Sensor

Located on the edge of the transmission above the flywheel ring gear, the G28 Engine Speed Sensor sends a signal to ECU pin T55/49 through an uncolored wire. The ECU then uses this information to control the flow of fuel, timig and boost. It also sends an alert to the G5 Tachometer in instrument cluster.

The sensor is used as a reference to correlate with the G40 Camshaft Position Sensor. The ecu needs to know when the crankshaft is TDC and where the camshaft is so it can start spark and injectors in the right way.

If this sensor fails, the ECU will display a P00160 code 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. The code won't show without the additional information supplied by other sensors (G4 or G40).

It's a bit tricky to test as there are various pins on the connector, and they all have different functions. The most effective method to test it is by measuring the resistance between the ECU and the sensor. It should read around 1000 ohms if the sensor is operating at its maximum. If you're having issues with this component, look for signs of coolant or oil in the connector bay.

2. Injectors

Yesterday, while accelerating at full speed from the highway paytoll i had massive power loss like the engine is out of gas or injectors are not firing at all. In the morning, i removed the spark plugs, three were soaked with gazoline and the 4th one was dry. When I crank the engine, there are no sparks i put tissue on the top of each of the injector holes and the 3 drenched with gazoline jump out but the 4th stays closed. I tested the ground connection on ECU pins 14/55,30/55 and 48/55 I get 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 not plugged in and is running fine when it is connected, but still has intermittent misfire issues at higher RPM. The coolant sensor Audikey (G62) even when unplugged, still shows an ice temperature of -49c. I also noticed that the oil gauge in the cockpit shows 2 bars when the actual pressure is 0.

I don't know what to do. I think I've eliminated everything else. I'm afraid i may have missed something. Let me know If you have any suggestions! TIA!

3. Fuel Pump

The fuel pump in the g28 can be activated by a signal from the RPM sensor. The GM-style sensor is identical to the G4 and both function 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 to do - just put your DMM in resistance mode and measure the resistance between pins 1 (with the bump on the connector's end up) and 2 (2nd from left on the black connector's end). They must be infinite Ohms.

4. ECU

The ECU of our 20vt turbo (3B AAN ABY) engines requires to know the position and speed of the crankshaft to make decisions regarding timing of the fuel injector, etc. It utilizes a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If either of these go bad you will get codes on the diagnostic scanner which could cause engine shut down.

The signs of a malfunctioning G28 sensor include an inaccurate gearbox rev counter and gears that shift faster than normal and/or misfiring when you are in gear. It is possible that the sensor is failing and needs to be replaced if you experience any of these signs. The good news is that they are very affordable and readily available, especially if you're looking at the Bosch unit like ours. Alternately, the GM version of this unit is also a great option.

5. Tachometer

A faulty engine speed sensor could be the reason behind numerous issues in your vehicle. It's a vital component of the audi a3 key fob's transmission since it relays information to the ECU about how fast or slow the car's crankshaft is spinning. If the sensor fails, it could cause problems for the transmission, as well as the rest of the car's components.

The G5 engine sensor is located near the edge of the transmission, over the flywheel ring. It sends an electrical signal through gray wire to ECU pin T55/49. The ECU utilizes this signal to control fuel and boost, and also timig. It also sends it to the G5 Tachometer located in the instrument cluster. You can check the sensor for any failure by checking the continuity between it and the tachometer, between ECU pin T55/49 and the instrument cluster connection to pin T6a/1 (trace [79trace [79]) and between T6a/1 and the instrument cluster pin T26a/12. You should see around 1000 ohms of resistance between those points. This is the same across the audi spare key 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.