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

Charles the Humble Technician teaches how to replace the G28 Engine Speed Sensor. This sensor is situated near the transmission's edge over the flywheel gear. It sends a message to the ECU through the grey wire T55/49 and then to the tachometer in the instrument cluster.

1. Engine Speed Sensor

The sensor is located at the edge of the transmission just above the flywheel ring gear, the G28 Engine Speed Sensor sends a signal to ECU pin T55/49 through a grey wire. The ECU then utilizes this information to regulate the flow of fuel, timig and boost. It also sends an indicator to the G5 Tachometer located in the instrument cluster.

The sensor is used to connect the G40 Camshaft position Sensor. The ecu needs to know when the crankshaft reached TDC and also where the camshaft lies so that it can activate the spark and injectors.

If this sensor fails when it fails, the ECU will display a P00160 error message. This indicates that the Crank Shaft is out of alignment with the Intake Camshaft. It could also indicate an issue with the chain or a jumped chain link in the upper timing chain. However, the code won't appear on its own, without additional information from other sensors (G4 and G40).

It can be a bit difficult to test since there are different pins on the connector, and each one has different functions. The best method for doing this is by measuring the resistance between the ECU and the sensor. When the sensor is fully functional, it should read approximately 1000 ohms. Check for evidence of coolant or oil in the connector bay if there are issues with this component.

2. Injectors

Yesterday, when i was accelerating to the fullest speed from highway paytoll i had an abrupt drop in power like the engine is running out of gas or injectors are not firing at all. I pulled out the spark plugs this morning, three were drenched in gasoline and the fourth was unclean. When I crank the engine with no sparks, I put a piece of tissue on the top of each hole in the injector, the 3 drenched with gazoline leap out, however the 4th stay closed. I inspected the ground connection on ECU pins 14/55/30/55/48/55/14/55/48/ I get zero Ohm. I'm assuming that the issue is elsewhere.

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 connected but it still is experiencing intermittent misfires at higher RPM. The coolant sensor (G62), even if it is not plugged in, shows temperatures of -49c. Also i noticed that the gauge for oil pressure in the cockpit shows 2 bar, whereas the actual pressure is 0.0 when i rev the engine.

I'm not sure what to do. I believe that I've ruled everything else out. I'm worried that i might have missed something. If anyone has any ideas please share them! TIA!

3. Fuel Pump

The fuel pump in the g28 can be activated by a signal from the RPM sensor. The GM-style transmitter is similar to the G4 sender and works on the 80,100,200, UrS, and RS2 vehicles. It is easy to find a spare in a wrecking shop or parts store. It is easy to test them - just switch your DMM into resistance mode and test the distance between pins 1 and 2 (with the bump at the connector end facing upwards). They must be infinite Ohms.

4. ECU

The ECU of our 20vt turbo (3B AAN ABY ADU) engines needs to know 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 either of these go bad you will get codes on the diagnostic scanner that could cause engine shut down.

A malfunctioning G28 sensor could result in an inaccurate speed counter for your gearbox, a gearbox that shifts more quickly than normal, and/or a misfire in gear. If you are experiencing any of these problems, it is most likely that your sensor is deteriorating and requires replacement key for audi. The good thing is that they are quite affordable and easy to find, especially in the case of a Bosch sensor, like ours. If you prefer, GM's version of this part would be a good option.

5. Tachometer

A malfunctioning engine speed sensor could be the reason behind a slew of problems in your vehicle. It's a crucial component of the transmission in your audi new key, as it transmits information to the ECU about how fast or slowly the engine of the car is spinning. This sensor could cause the transmission to malfunction and other components of the car to be affected.

The G5 engine sensor is located at the outskirts of transmission, above the flywheel ring. It transmits signals via a gray wire to the ECU pin T55/49. The ECU utilizes this signal to regulate the amount of fuel and boost, as well as timig. It also transmits it to the G5 Tachometer inside the instrument cluster. You can check for sensor failure by checking continuity from the sensor to the tachometer. Also, you can verify continuity between pin T55/49 of the ECU and pin T6a/1 of the instrument cluster (trace [79trace [79]), and between pin T6a/1 as well as pin T26a/12. It should show around 1000 ohms of resistance between those points. This is the same across the Audi 80-100-200-RS2 series, starting from the 1985 MC up to the 1997 UrS AN and 1995 RS2 Du, so you might find them in wrecking yards.