How to Replace an Audi G28 Engine Speed Sensor

In this video, Charles the humble mechanic demonstrates how to replace the G28 engine speed sensor. This sensor is situated near the transmission's edge, above the flywheel gear. It transmits a signal the ECU via the grey wire (T55/49), then to the tachometer in the instrument cluster.

1. Engine Speed Sensor

The grey wire is situated on the outside of the transmission, directly above the flywheel ring. The sensor sends signals through 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 located in the instrument cluster.

The sensor is used as a reference for comparing with the G40 Camshaft Position Sensor. The ecu has to be aware of when the crankshaft has reached TDC, and the position of the camshaft, in order to activate the spark and injectors.

If this sensor fails, the ECU will throw a P00160 code which means the Crank Shaft and Intake Camshaft aren't in sync, possibly indicating the chain stretching or a jump link on the upper chain of timing. The code won't show without the additional information provided by other sensors (G4 or G40).

It is a little tricky to test because there are different pins on the connector and they all have different functions. The most effective method to test it is by measuring the resistance between the ECU and the sensor. It should read around 1000 ohms when the sensor is operating at its maximum. If you are having problems with this component, look for evidence of oil or coolant in the connector bay.

2. Injectors

Yesterday, while accelerating at full speed from the highway paytoll, I experienced an abrupt drop in power as if the engine was running out of gas or the injectors are not firing anymore. I pulled out the spark plugs this morning, 3 were soaked in gasoline, and the fourth was dry. When I start the engine without sparks i put tissue on the top of each hole in the injector and the 3 that were drenched in gazoline pop out, but the 4th stays shut. I tried to test the ground connections of ECU pins 14,30, and 48/55. I got zero ohm. I think the issue is elsewhere.

I also tried to reset the PID without success. The car can start if the G28 is unplugged and runs fine when it is connected but it still is experiencing intermittent misfires at higher RPM. The coolant temperature sensor (G62) shows the wrong temperature of that is -49c even after unplugging it. I also noticed that the oil pressure gauge in the cockpit is showing 2 bar when the actual pressure is 0.0 when i rev the engine.

I'm not certain what to do, i believe that i've completely ruled out all other possibilities. But i'm worried replacement car key audi that I might have missed something. If anyone has suggestions, please share them! TIA!

3. Fuel Pump

The fuel pump in 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 which is why you can easily locate one at a wrecking yard or at a parts store. Test them out by putting your DMM in resistance mode and measure between pins 1 (with the bump on the connector's end up) and 2 (2nd from left on the black connector's end). They should be infinite Ohms.

4. click here ECU

The ECU of our 20vt turbo (3B AAN ABY ADU) engines needs to know the speed and position of the audi a3 key replacement near me crankshaft to make decisions regarding timing of fuel injectors, etc. It makes use of a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If you are experiencing issues with either of these, the diagnostic scanner will show codes that could lead to an engine shut down.

A failing G28 sensor can cause an inaccurate speed counter for the gearbox, a gearbox that shifts more quickly than normal, and/or a misfire in gear. If you have any of these issues it is most likely audi a1 car key that your sensor is going bad and should be replaced. They're cheap 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 an option.

5. Tachometer

A damaged engine sensor could cause a number of problems in your vehicle. It's an essential component of the transmission in your Audi, as it transmits information to the ECU regarding how fast or slow the engine is turning. This sensor could cause the transmission to fail and other components in the car to be affected.

The G5 engine speed sensor is located on the edge of the transmission above the flywheel ring gear. It transmits a signal to the ECU at pin T55/49 through a check here grey wire. The ECU utilizes this signal to control fuel and boost, and also timig. It also transmits it to the G5 Tachometer in instrument cluster. You can check the sensor for failure by checking continuity between it and the tachometer. You can also check continuity between ECU pin T55/49 and the instrument cluster connection to pin T6a/1 (trace [79trace [79]) as well as between T6a/1, and the instrument cluster pin T26a/12. You should see approximately 1000 ohms of resistance between these two points. This is the same 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, so you might find good ones in wrecking yards.