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

Charles the Humble Technician teaches how to replace the G28 Engine Speed Sensor. The sensor is located on the edge of the transmission just above the flywheel ring gear. It sends a message to the ECU through a grey wire T55/49, then to the tachometer located on the instrument cluster.

1. Engine Speed Sensor

The grey wire is located on the outside of the transmission, above the flywheel ring. This sensor sends a signal via the grey wire to pin T55/49. The ECU uses this information to regulate the amount of fuel and boost. It also sends an alert to the G5 Tachometer within the instrument cluster.

The sensor is used to connect the G40 Camshaft position Sensor. The ecu must be aware when the crankshaft is TDC and where the camshaft is so it can trigger spark and injectors accordingly.

If this sensor fails, the ECU will display an error car key Replacement audi code P00160. This indicates that the Crank Shaft is out of sync with the Intake Camshaft. It could also indicate a chain stretch or a jumped chain link in the upper chain. The code won’t show without the additional information supplied by other sensors (G4 or G40).

It can be a bit difficult to test since there are different pins on the connector, 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 around 1000 ohms when the sensor is at full operation. If you’re having issues with this sensor, look for evidence of coolant or oil in the connector bay.

2. Injectors

Yesterday accelerating full speed from highway paytoll i had a big cut in power as if the engine was running out of gas or injectors aren’t firing anymore. I took out the spark plugs this morning and found that 3 were soaked in gasoline, and the 4th was dry. When I crank the engine with no sparks i put tissue on top of each injector hole and the 3 drenched with gazoline leap out, however the 4th stay closed. I tested the ground connection of ECU pins 14,30, and 48/55. I found zero ohm. I’m assuming that the issue is elsewhere.

I also tried to reset PID without success. The car can start if the G28 is not plugged in and runs fine when it is plugged in, but still has intermittent misfire issues at higher RPM. The coolant temperature sensor (G62) shows the wrong temperature of that is -49c even after unplugging it. Also i noticed that the gauge for oil pressure 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 believe that i’ve ruled out everything else. However, i’m afraid that I might have missed something. If anyone has suggestions, please share them! TIA!

3. Fuel Pump

The fuel pump on the g28 is 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. You can easily find the spare in a salvage shop or parts store. It is simple to test them – simply put your DMM into resistance mode and determine the distance between pins 1 and 2 (with the bump at the connector’s end facing up). They should be infinite Ohms.

4. ECU

The ECU in our 20vt turbo (3B AAN ABY ADU) engines requires to be aware of the position and speed the crankshaft in order to make a decision about fuel injector car key replacement audi timing, etc. It makes use of a Crank Position Sensor G4 and an Engine Speed Sensor G28 to achieve this. If you have a problem with either one of these, the diagnostic scanner will display the codes that could trigger the engine shutting down.

Some of the signs of a failing G28 sensor are an inaccurate rev counter in the gearbox, gears shifting quicker than normal and/or a misfire when you’re in gear. If you are experiencing any of these issues, it is likely that your sensor is going bad and should be replaced. The good news is that they are very cheap and easy to find, especially in the case of a Bosch sensor, which is what ours are. You can also choose the GM version of this unit is also a good option.

5. Tachometer

A malfunctioning engine speed sensor could be the cause of a slew of problems in your car key replacement audi. It’s an essential component of the transmission of your Audi because it relays information to the ECU regarding how fast or slowly the engine is turning. When this sensor fails, it could affect the performance of the transmission as well as the other car’s components.

The G5 engine sensor is located at the outskirts of the transmission, just above the flywheel ring. It transmits signals via a gray wire to the ECU pin T55/49. The ECU uses this signal to regulate fuel and boost, as well as timig. It also transmits it to the G5 Tachometer in instrument cluster. You can test the sensor for any failure by checking the 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 of resistance between those two pins. This part is common across the Audi 80-100-200-RS2 range, from the 1985 MC all the way up to the 1997 UrS AN and the 1995 RS2 DU You may also find some good ones in wrecking yards.