"Ask Me Anything": Ten Answers To Your Questions About Audi G28

How to Replace an audi replacement key service near me G28 Engine Speed Sensor

Charles the Humble Technician teaches you how to replace the G28 Engine Speed Sensor. This sensor is located near the edges of the transmission, above the flywheel ring gear. It transmits a signal to the ECU via the grey wire (T55/49), then to the tachometer in 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 signals to ECU pin T55/49 through the grey wire. 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 serves as a reference to correlate with the G40 Camshaft Position Sensor. The ecu has to know when the crankshaft reached TDC and also the position of the camshaft, in order to activate the spark and injectors.

If this sensor fails, the ECU will display an error code P00160 which indicates that the Crank Shaft and Intake Camshaft are out of sync and could indicate the chain is stretched or a jump link on the upper chain of timing. The code won't show without the additional information supplied by other sensors (G4 or G40).

It can be a bit difficult to test because there are several pins on the connector, and they all have different functions. The best way to do it is by measuring the resistance between the ECU and the sensor. If the sensor is operational, it should be reading around 1000 ohms. If you are having problems with this part, check for evidence of oil or coolant 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 aren't firing anymore. I pulled out the spark plugs this morning and found that 3 were drenched in gasoline and the fourth was dry. When I start the engine with no sparks i put tissue on top of each injector hole and the 3 that were drenched in gazoline pop out, but the 4th one stays shut. I tested the ground connection on ECU pins 14/55/30/55/48/55/14/55/48/ I get 0ohm. So i assume the problem is in another place.

I also tried to reset PID but without success. The car will start when the G28 is unplugged and is running fine when it is plugged in, but still has intermittent misfire issues at higher RPM. The coolant sensor (G62) even if it is not plugged in, shows an ice temperature of -49c. Also, i noticed that the oil pressure gauge in the cockpit is showing 2 bar when 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 chime in! TIA!

3. Fuel Pump

The fuel pump on the g28 is activated by a signal by the RPM sensor. The GM-style sensor is the same as the G4 and both function in the 80, 100, 200, UrS and Audi car key replacement RS2 cars which is why you can easily locate one at a salvage yard or at a parts store. Test them out - put your DMM in resistance mode and take measurements between pins 1 (with the bump on the connector's end up) and 2 (2nd from left on the black connector's side). They should be infinite Ohms.

4. ECU

The ECU of our 20vt turbo (3B AAN ABY ADU) engines must be aware of the position and speed the crankshaft in order to make a decision about timing of the fuel injector, etc. It uses a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If you are experiencing issues with either one of these, the diagnostic scanner will show the codes that could trigger the engine shutting down.

A failing G28 sensor could cause an inaccurate gearbox speed counter and a gearbox which shifts more quickly than normal, and/or a misfire while in gear. If you experience any of these problems, it is likely that your sensor is failing and requires audi key replacement. The good news is that they are very cheap and readily available, especially when you're looking at the Bosch model, which is what ours are. Alternatively, GM's version of this part would be an excellent choice.

5. Tachometer

A malfunctioning engine speed sensor could be the cause of a slew of problems in your vehicle. It's an essential component of the transmission of your audi a1 key fob because it relays information to the ECU about how fast or slowly the engine of the car is turning. This sensor can cause the transmission to malfunction and other components in the car to be affected.

The G5 engine sensor is located at the outskirts of the transmission, just above the flywheel ring. It sends signals via a gray wire to the ECU pin T55/49. The ECU utilizes this signal to regulate the amount of fuel and boost, and also timig. It also transmits it to the G5 Tachometer inside the instrument cluster. You can check for sensor failure by examining the continuity of the sensor to the tachometer. Also, you can check continuity between pin T55/49 of the ECU and pin T6a/1 of the instrument cluster (trace [79trace [79]), and between pin T6a/1 and pin T26a/12. There should be an average resistance of 1000 ohms between these points. This is the same across the audi key shell 80-100-200-RS2 model, ranging from the 1985 MC up to the 1997 UrS An and 1995 RS2 Du So, you may find some good ones in wrecking yards.