How to Replace an
audi connect key G28 Engine Speed Sensor
Charles the Humble Technician shows you how to replace the G28 Engine Speed Sensor. The sensor is situated at the top of the transmission above the flywheel ring gear. It transmits a signal the ECU via a grey wire (T55/49) and then to the tachometer located in the instrument cluster.
1. Engine Speed Sensor
The sensor is located at the edge of the transmission above the flywheel ring gear the G28 Engine Speed Sensor sends signals to ECU pin T55/49 using the grey wire. The ECU then utilizes this information to regulate the flow of fuel, timig and boost. It also sends an alert to the G5 Tachometer in instrument cluster.
The sensor serves as a reference point to connect 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 trigger spark and injectors accordingly.
If this sensor fails when it fails, the ECU will display an error code P00160. This means that the Crank Shaft is out of line with the Intake Camshaft. It could also be a sign of the possibility of a chain stretch or jumpy chain link in the upper timing chain. The code won't appear without the additional information provided by other sensors (G4 or G40).
It's a bit tricky to test as there are various connector pins, and each has its own functions. The best way to do it is by measuring the resistance between the ECU and the sensor. It should read approximately 1000 ohms when the sensor is at full operation. If you're experiencing issues with this component, look for evidence of oil or coolant in the connector bay.
2. Injectors
Yesterday, while accelerating from the highway paytoll at maximum speed, i noticed a huge drop in power. It was like the engine was running out of gas. Or, my injectors weren't firing. Today, i pulled out the spark plugs, 3 were soaked with gazoline and the fourth one was dry. When I crank the engine without sparks i put tissue on the top of each hole in the injector and the 3 that were drenched in gazoline leap out, however the 4th stays shut. I checked the ground connection of ECU pins 14,30 and 48/55. I found zero ohm. I think the issue is elsewhere.
I also tried to reset the PID but with no luck. The car will start when the G28 is unplugged, and it runs fine with the G28 plugged in. However the intermittent misfire issue persists at higher RPM. The coolant temperature sensor (G62) shows the wrong temp value -49c, even if I unplug it. Also i noticed that the oil pressure gauge in the cockpit shows 2 bar,
Audi Spare Key whereas the actual pressure is 0.0 when i rev the engine.
I'm not sure what to do. I think I've eliminated everything else. I'm concerned that i may 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 by the RPM sensor. The GM-style transmitter is the same as the G4 and both function in the 80 100, 200, UrS and RS2 cars which is why you can easily locate one at a junkyard or from a parts store. Testing them is easy 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 connector's end). They must 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 to make decisions regarding timing of fuel injectors, etc. It utilizes 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 display codes that could cause the engine shutting down.
A malfunctioning G28 sensor could cause an inaccurate speed counter for your gearbox, a gearbox that shifts more quickly than normal, or an unfire when in gear. It is probable that the sensor is failing and needs to be replaced if you encounter any of these symptoms. They are cheap and easy-to-find particularly in the case of an Bosch sensor like ours. Alternately,
audi spare Keys GM's version this part would be an option.
5. Tachometer
A failing engine sensor could cause a myriad of issues in your vehicle. It is an important part of the transmission of your
audi a1 key since it sends information to the ECU on how fast or slow the engine of the car is spinning. This sensor can cause the transmission to malfunction and other
audi car key cover components to be affected.
The G5 engine sensor is located at the outskirts of the transmission, over the flywheel ring. It sends signals via an uncolored wire to the ECU pin T55/49. The ECU then uses and processes this signal to control fuel, timig, and boost as well as transmitting it to the G5 Tachometer located in the instrument cluster. You can test for sensor failure by examining the continuity of 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 [79]), and between pin T6a/1 as well as pin T26a/12. You should see a resistance of approximately 1000 ohms between these points. This is the same across the
audi spare key cost 80-100-200-RS2 series, starting from the 1985 MC all the way up to the 1997 UrS AN and 1995 RS2 DU You may also find them in wrecking yards.