Ten Things You Learned At Preschool, That'll Aid You In Audi G28

How to Replace an Audi G28 Engine Speed Sensor

Charles the Humble Technician teaches 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 sends a signal to the ECU via a grey wire (T55/49), then to the tachometer within the instrument cluster.

1. Engine Speed Sensor

It is located on the outside of the transmission, 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 utilizes this information to regulate the flow of fuel, timig and boost. It also sends a signal to the G5 tachometer in the instrument cluster.

The sensor is used as a reference to correlate 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 in the right way.

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 indicate the possibility of a chain stretch or jump in the chain link of the upper chain. The code won't show without the additional information provided by other sensors (G4 or G40).

It's a bit tricky to test as there are various 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 approximately 1000 ohms when it is in full operation. If you're experiencing issues with this part, check for signs of oil or coolant in the connector bay.

2. Injectors

Yesterday accelerating full speed from highway paytoll i had massive power loss as if the engine was running out of gas or the injectors aren't firing at all. In the morning, i removed the spark plugs. Three were drenched with gazoline the fourth one was dry. I put a piece of tissue over each injector hole, and when I start the engine with no sparks, the 3 with gazoline jump right out. The 4th one stays shut. I checked the ground connection on ECU pins 14/55/30/55/48/55/14/55/48/ i get 0ohm. So i assume the problem is in another place.

I also tried to reset PID without success. The car can start when the G28 is unplugged and it runs perfectly when it is connected, but still is experiencing intermittent misfires at higher RPM. The coolant sensor (G62), even when it is unplugged, shows an ice temperature of -49c. Also, i noticed that the gauge for oil pressure in the cockpit shows 2 bar when the actual pressure is 0.0 when I crank up the engine.

I don't know what to do. I think I've all other possibilities out. I'm afraid i may have missed something. If anyone has suggestions, please share them! TIA!

3. Fuel Pump

The fuel pump in the g28 can be activated by a signal sent from the RPM sensor. The GM-style transmitter is identical to the G4 sender and both work 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 by putting your DMM in resistance mode and measure the resistance between pins 1 (with the bump on the connector's side up) and 2 (2nd from the left on the black connector's side). They must be infinite Ohms.

4. ECU

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

A malfunctioning G28 sensor could cause an inaccurate speed counter for the gearbox or a gearbox that shifts more quickly than normal, and/or an unfire when in gear. If you experience any of these problems, it is likely your sensor is failing and requires replacement. The good thing is that they are very affordable and easily accessible, especially when you're looking at a Bosch model, like ours. Alternatively, the GM here version of this unit is also a good option.

5. Tachometer

A malfunctioning engine speed sensor could be the reason behind a slew of issues with your car. It's an essential component of the Audi's transmission as it sends information to the ECU about how fast or slow the vehicle's crankshaft is spinning. If the sensor fails, it can disrupt the performance of the transmission and the rest of the car's more info components.

The G5 engine get more info speed sensor is located on the edge of the transmission above the flywheel ring gear and sends a signal to the ECU at pin T55/49, via a grey wire. The ECU is then able to process this signal to control fuel, timig and boost and then sends it on to the G5 Tachometer located in the instrument cluster. You can test the sensor for any failure by checking the continuity between read more it and the tachometer, between ECU pin T55/49 and the instrument cluster connection via pin T6a/1 (trace [79]) and between pin T6a/1 and the instrument cluster pin T26a/12. It should show approximately 1000 ohms of click here resistance between those two pins. This is a common component across the Audi 80, 100, 200, UrS and RS2 range from 1985 MC until the 1997 UrS AAN and 1995 RS2 ADU, so the best ones could be available in wrecking yards.