It s The Ugly Truth About Audi G28

How to Replace an audi keyfob G28 Engine Speed Sensor

Charles the Humble Technician teaches how to replace the G28 Engine Speed Sensor. This sensor is located on the outside of the transmission, above the flywheel gear. It sends a message to the ECU through an uncolored wire T55/49, then to the tachometer located 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 using an uncolored wire. The ECU utilizes this information to control boost and fuel. It also sends an alert to the G5 Tachometer in instrument cluster.

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

If this sensor fails, the ECU will throw an error code P00160 which indicates that the Crank Shaft and Intake Camshaft are not in sync and could indicate chain stretch or a jumped link on 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 they all have different functions. The best method for doing this is by measuring the resistance between the ECU and the sensor. When the sensor is functional, it should read around 1000 ohms. 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 experienced massive power loss as if the engine was running out of gas or injectors are not firing anymore. Today, i pulled out the spark plugs, three were drenched in gazoline, the fourth was dry. When I start the engine, there are no sparks, I put a piece of tissue on the top of each of the injector holes, the 3 drenched with gazoline pop out, but the 4th stay shut. I checked the ground connection of ECU pins 14,30 and 48/55. I found 0ohm. Therefore, i think the issue is elsewhere.

I also tried to reset the PID with no success. The car will start when the G28 is disconnected, but it is running fine with the G28 connected. However, the intermittent misfire problem persists at higher RPM. The coolant sensor (G62) even if it is not plugged in, shows a temperature of -49c. Also, i noticed that the oil pressure gauge in the cockpit shows 2 bar, whereas 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. But i'm worried that I might have missed something. Please let me know if you have any ideas! TIA!

3. Fuel Pump

The fuel pump of the g28 receives signals 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 the spare in a salvage shop or a parts store. It is easy to test them: simply switch your DMM into resistance mode and measure the distance between pins 1 and 2 (with the bump on the connector's edge facing upwards). They must be infinite Ohms.

4. ECU

Our 20vt turbo (3B AAN, audi Key replacement ABY and ADU) engines are equipped with an ECU that needs to know the position and speed of the crankshaft to make decisions about timing of the fuel injectors, etc. To accomplish this, it utilizes a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If you have a problem with either of these, the diagnostic scanner will display the codes that could trigger an engine shut down.

Some of the symptoms of a malfunctioning G28 sensor include an inaccurate rev counter in the gearbox and gears that shift faster than normal and/or a misfire when you're in gear. If you experience any of these problems, it is likely your sensor is failing and should be replaced. They're cheap and easy to find especially in the case of an Bosch model like ours. Alternately, GM's version this part would be an option.

5. Tachometer

A faulty engine speed sensor could be the cause of numerous problems in your car. It is a crucial part of your audi advanced key tt key fob - atomcraft.ru -'s transmission, because it communicates to the ECU about how the car's crankshaft is turning. This sensor could cause the transmission to fail and other car components to be affected.

The G5 engine sensor is located at the edge of the transmission, over the flywheel ring. It sends an electrical signal through an uncolored wire to the ECU pin T55/49. The ECU uses this signal to control fuel and boost, and also to timigrate. It also sends it to the G5 Tachometer inside the instrument cluster. You can test for sensor failure by examining the continuity from the sensor to the tachometer. Additionally, you can examine the continuity between pins T55/49 of the ECU and pin T6a/1 of the instrument cluster (trace [79]), and between pin T6a/1 as well as pin T26a/12. It should show approximately 1000 ohms of resistance between those two pins. This part is common across the audi car key replacement 80-100-200-RS2 series, starting from the 1985 MC up to the 1997 UrS AN and the 1995 RS2 Du, so you might find good ones in wrecking yards.