"Ask Me Anything:10 Responses To Your Questions About Audi G28

How to Replace an new audi key G28 Engine Speed Sensor

In this video, Charles the Humble Mechanic shows how to replace the G28 engine speed sensor. The sensor is situated near the edges of the transmission, above the flywheel ring gear. It transmits a signal to the ECU via an uncolored wire T55/49, then to the tachometer on the instrument cluster.

1. Engine Speed Sensor

It is located on the outside of the transmission just above the flywheel ring gear, the G28 Engine Speed Sensor sends an electrical signal to ECU pin T55/49 via a grey wire. The ECU uses this information to regulate boost and fuel. It also sends signals to the G5 Tachometer located in the instrument cluster.

The sensor is used to connect with the G40 Camshaft position Sensor. The ecu needs to know when the crankshaft is TDC and the location of the camshaft so it can activate spark and injectors accordingly.

If this sensor fails to function, the ECU will display an error code P00160. This indicates that the Crank Shaft is not in line with the Intake Camshaft. It could also be a sign of the possibility of a chain stretch or jump in the chain link of the upper chain of timing. However the code will not appear on its own, without additional information from other sensors (G4 and G40).

It's a bit tricky to test since there are several 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. If the sensor is operational, it should read around 1000 ohms. If you are having problems with this component, look for signs of coolant or oil in the connector bay.

2. Injectors

Yesterday, when accelerating from highway paytoll at a high speed I noticed a massive reduction in power. It was like the engine had run out of gas. Or my injectors were not firing. Today, i pulled out the spark plugs. Three were drenched in 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 three with gazoline jump right out. The 4th one remains shut. I tested the ground connection on ECU pins 14/55/30/55/48/55/14/55/48/ I got zero Ohm. I assume that the problem is elsewhere.

I also tried to reset the PID without success. The car will start when 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 value of -49c, even if I unplug it. I also noticed that the oil gauge in the cockpit shows 2 bars while the actual pressure is 0.

I'm not certain what to do, as i feel i have pretty much ruled out everything else. But i'm worried that I might have missed something. If anyone has suggestions, please chime in! TIA!

3. Fuel Pump

The fuel pump in the g28 is activated by a signal from the RPM sensor. The GM-style transmitter functions similarly to the G4 sender and works on the 80,100,200, UrS, and RS2 vehicles. You can easily find an extra in a wrecking shop or a parts store. It is simple to test them: simply put your DMM into resistance mode and test the distance between pins 1 and 2 (with the bump at the connector end facing up). They should be infinite Ohms.

4. ECU

The ECU in our 20vt turbo (3B AAN ABY) engines must know both the speed and position of the crankshaft to make decisions regarding fuel injector timing, etc. To accomplish this, it makes use of a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If either of these go wrong, you will receive codes on the diagnostic scanner which can lead to engine shutdown.

A damaged G28 sensor could result in an inaccurate gearbox speed counter or a gearbox that shifts more quickly than normal, or a misfire while in the gear. If you experience any of these issues it is likely that your sensor is deteriorating and requires replacement audi keys. They're inexpensive and easy to locate, especially if they're an Bosch sensor like ours. If you prefer, GM's version of this part is an excellent choice.

5. Tachometer

A failing engine speed sensor could be the reason behind numerous problems in your car. It's a crucial component of the transmission of your Audi, as it transmits information to the ECU regarding how fast or slow the engine of the car is spinning. This sensor could cause the transmission to fail and other components of the car to be affected.

The G5 engine speed sensor is located on the outside of the transmission just above the flywheel ring gear. It sends a signal to the ECU at pin T55/49 through a grey wire. The ECU is then able to process this signal to control fuel, timig, and boost as well as transmitting it to the G5 tachometer in the instrument cluster. You can check the sensor for failure by checking continuity between it and the tachometer, between the ECU pin T55/49 and the instrument cluster connection on pin T6a/1 (trace [79]) and between T6a/1 and the instrument cluster pin T26a/12. It should show approximately 1000 ohms resistance between these two points. This is a typical component across the audi a3 key fob replacement a3 spare key audi; www.google.com.gi, 80 100, 200, UrS and RS2 range from 1985 MC to the 1997 UrS AAN and 1995 RS2 ADU. Good ones could be available in wrecking yards.