How to Replace an audi car key cover G28 Engine Speed Sensor

Charles the Humble Technician shows you how to replace the G28 Engine Speed Sensor. This sensor is located at the edge of transmission over the flywheel gear. It sends a message to the ECU via a grey wire T55/49, then to the tachometer located on the instrument cluster.

1. Engine Speed Sensor

It is located on the outside of the transmission just above the flywheel ring gear the G28 Engine Speed Sensor sends a signal to ECU pin T55/49 via a grey wire. The ECU then uses this information to control the boost, fuel, and timig. It also sends an alert 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 located so that it can activate spark and injectors accordingly.

If this sensor fails, the ECU will display an error code P00160. This means that the Crank Shaft is not in alignment with the Intake Camshaft. It could also indicate an issue with the chain or a jump in the chain link of the upper chain of timing. The code will not appear without the additional information provided by other sensors (G4 or G40).

Testing is a bit tricky as there are two different pins for the connector and they have different functions however the best method of testing it is by measuring resistance between the sensor and the ECU. It should read about 1000 ohms when the sensor is operating at its maximum. If you're having issues with this sensor, look for evidence of oil or coolant in the connector bay.

2. Injectors

Yesterday accelerating full speed from highway paytoll i had an abrupt drop in power as if the engine was running out of gas or the injectors are audi tt key fob not working firing at all. I took out the spark plugs this morning, 3 were soaked with gasoline and the fourth was dry. I put tissue over each hole in the injector and when i turn the engine on without sparks, the ones with gazoline jump out. The 4th one remains closed. I tested the ground connection of ECU pins 14,30 and 48/55. I found zero ohm. So i assume the problem is elsewhere.

I also tried to reset the PID without success. The audi car key replacement will start when the G28 is disconnected, but it is running fine with the G28 plugged in. However the intermittent misfire issue continues to occur at higher RPM. The temperature sensor for the coolant (G62) shows the wrong temp value -49c, even if I unplug it. Also i noticed that the gauge for oil pressure in the cockpit shows 2 bar while the actual pressure is 0.0 when I crank up the engine.

I'm not certain what to do, i feel i have pretty much eliminated everything else. I'm afraid i may have missed something. Let me know should you have any suggestions! TIA!

3. Fuel Pump

The fuel pump of the g28 gets a signal from the RPM sensor. The GM-style sender is the same as the G4 and they both work in the 80 100, 200, UrS and RS2 cars which is why you can easily locate one at a salvage yard or in a local parts store. It is simple to test them - 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 the left on the black connector's end). They must be infinite ohms.

4. ECU

Our 20vt turbo (3B AAN, ABY and ADU) engines have an ECU that has to know the speed and position of the crankshaft in order to make decisions about fuel injector timing etc. It makes use of a Crank Position Sensor G4 and an Engine Speed Sensor G28 to achieve this. If you encounter a problem with either one of these, the diagnostic scanner will display codes that could lead to an engine shut down.

The signs of a failing G28 sensor include an inaccurate rev counter for the gearbox and gears that shift faster than normal and/or misfiring when you're in gear. If you experience any of these issues it is likely your sensor is deteriorating and needs replacing. They're cheap and easy to find, especially when they're an Bosch unit like ours. Alternatively, GM's version of this part is an option.

5. Tachometer

A failing engine speed sensor could be a cause for many issues with your vehicle. It's an essential component of the transmission in your audi key fob replacement cost since it sends information to the ECU regarding how fast or slow the engine of the car is turning. This sensor could cause the transmission to fail and other car components to be affected.

The G5 engine speed sensor is located at the edge of the transmission, above the flywheel ring gear and sends a signal directly to the ECU at pin T55/49, via an uncolored wire. The ECU utilizes this signal to regulate the flow of fuel and boost as well as timig. It also relays it to the G5 Tachometer located in the instrument cluster. You can test key for audi sensor failure by examining the continuity of the sensor to the tachometer. You can also 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. You should see a resistance of approximately 1000 ohms between these points. This is the same across the audi replacement key service 80-100-200-RS2 range, from the 1985 MC all the way up to the 1997 UrS AN and 1995 RS2 Du So, you may find them in wrecking yards.