How to Replace an audi spare key G28 Engine Speed Sensor

Charles the Humble Technician teaches you how to replace the G28 Engine Speed Sensor. The sensor is located on the outside of the transmission just above the flywheel gear. It transmits a signal to the ECU via the grey wire (T55/49) and then to the tachometer within the instrument cluster.

1. Engine Speed Sensor

The grey wire is situated at the edges of the transmission, above the flywheel ring. The sensor sends a signal via the grey wire to pin T55/49. The ECU utilizes this information to control the amount of fuel and boost. It also sends an indication to the G5 tachometer inside the instrument cluster.

The sensor is used to correlate the G40 Camshaft position Sensor. The ecu needs to know when the crankshaft is TDC and where the camshaft is located so that it can start spark and injectors accordingly.

If this sensor fails the ECU will throw a P00160 code which means the Crank Shaft and Intake Camshaft are not in sync and possibly indicating the chain is stretched or a jump link on the upper chain of timing. However the code will not be displayed on its own without additional information from other sensors (G4 and G40).

Testing is a bit challenging as there are two different connector pins, and they perform different functions but the most effective way to test it is to measure the resistance between the sensor and the ECU. It should read approximately 1000 ohms if the sensor is in full operation. If you are having problems with this sensor, look for signs of coolant or oil in the connector bay.

2. Injectors

Yesterday, as i was accelerating off the highway paytoll at maximum speed I noticed a significant drop in power. It was as if the engine was running out of gas. Or my injectors were not firing. Today, i pulled out the spark plugs. Three were soaked with gazoline and the 4th one was dry. When I start the engine with no sparks i put tissue on the top of each of the injector holes and the 3 that were drenched in gazoline leap out, however the 4th one stays shut. I inspected the ground connection on ECU pins 14/55, 30/55 and 48/55. I got 0ohm. I think the issue is elsewhere.

I also tried to reset the PID with no success. The car will start when the G28 is unplugged, and it runs fine with the G28 plugged in. However the intermittent misfire issue still occurs at higher RPM. The coolant sensor (G62) even if it is not plugged in, shows a temperature of -49c. Also, i noticed that the oil pressure gauge in the cockpit is showing 2 bar, whereas the actual pressure is 0.0 when I crank up the engine.

I don't know what to do. I think I've all other possibilities out. However, i'm afraid that i might have missed something. Please let me know if you have any ideas! 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 and both function in the 80, 100, 200, UrS and RS2 cars so you can easily find one at a junkyard or from a parts store. It is easy to test them - just switch your DMM into resistance mode and measure the distance between pins 1 and 2 (with the bump at the connector's end facing up). They must be infinite Ohms.

4. ECU

The ECU of our 20vt turbo (3B AAN ABY) engines needs to know both the position and speed the crankshaft in order to make a decision about timing of the fuel injector, etc. It utilizes a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If you encounter a problem with either of these sensors, the diagnostic scanner will show codes that could lead to an engine shut down.

Some of the signs of a failed G28 sensor are an inaccurate gearbox rev counter the gears are shifting faster than normal, and/or a misfire when you're in gear. If you have any of these issues it is likely that your sensor is going bad and requires replacement key audi q5 key - https://hosimkig.gwangju.ac.Kr/bbs/board.php?bo_table=free&wr_id=1198016 -. The good news is they are very affordable and easy to find, especially in the case of an Bosch unit which is what ours are. You can also choose the GM version of this part is also a good option.

5. Tachometer

A failing engine sensor could cause a number of problems in your vehicle. It's a vital component of your audi spare keys'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 components of the car to be affected.

The G5 engine sensor is located at the outskirts of the transmission, over the flywheel ring. It sends a signal via a gray wire to the ECU pin T55/49. The ECU uses this signal to regulate fuel and boost, and also timig. It also sends it to the G5 Tachometer located in the instrument cluster. You can test the sensor for failure by checking continuity between it and the tachometer, between the ECU pin T55/49 and the instrument cluster connection to pin T6a/1 (trace [79]) as well as between T6a/1, and the instrument cluster pin T26a/12. It should show approximately 1000 ohms resistance between those two pins. This is a common component across the audi replacement key 80 100, 200, UrS and RS2 range from 1985 MC through the 1997 UrS AAN and 1995 RS2 ADU so good ones might be availble in wrecking yards.