The 3 Greatest Moments In Audi G28 History

How to Replace an audi a5 key fob G28 Engine Speed Sensor

Charles the Humble Technician shows you how to replace the G28 Engine Speed Sensor. This sensor is located at the edge of transmission over the flywheel gear. It transmits a signal 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 signals to ECU pin T55/49 using a grey wire. The ECU then utilizes this information to regulate the flow of fuel, Audi car Key timig and boost. It also sends a signal to the G5 tachometer in the instrument cluster.

The sensor is used to link with the G40 Camshaft position Sensor. The ecu needs to know when the crankshaft is TDC and where the camshaft is so it can trigger spark and injectors according to the situation.

If this sensor fails, the ECU will display a P00160 code which means the Crank Shaft and Intake Camshaft are out of sync and could indicate the chain is stretched 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 can be a bit difficult to test as there are several connector pins, and each has its own functions. The best way to do it is by measuring the resistance between the ECU and the sensor. When the sensor is operational, it should be reading approximately 1000 ohms. Look for evidence of coolant or oil in the connector bay if you have issues with this part.

2. Injectors

Yesterday accelerating full speed from highway paytoll, i experienced a big cut in power like the engine is out of gas or injectors are not firing any more. This morning i pull out the spark plugs, 3 were drenched with gazoline the fourth was dry. I put a piece of tissue over each hole in the injector and when i start the engine without sparks, the ones with gazoline jump 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 zero ohm. I'm assuming 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 plugged in but it still has the intermittent misfire issue at higher RPM. The coolant sensor (G62) even when it is unplugged, shows an ice temperature of -49c. I also noticed that the oil gauge in the cockpit shows 2 bars when the actual pressure is zero.

I'm not sure what to do. I think I've ruled everything else out. But i am afraid I may have missed something. Please let me know If you have any suggestions! TIA!

3. Fuel Pump

The fuel pump of the g28 receives a signal from the RPM sensor. The GM-style transmitter is identical to the G4 sender and works on the 80,100,200, UrS, and RS2 vehicles. It is easy to find an extra in a wrecking shop or a parts store. Test them out - put your DMM in resistance mode and measure between pins 1 (with the bump on the connector's side up) and 2 (2nd from left on the black end of the connector). They must be infinite Ohms.

4. ECU

The ECU in our 20vt turbo (3B AAN ABY) engines needs to be aware of the speed and position of the crankshaft to make decisions regarding timing of fuel injectors, etc. It uses a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If you are experiencing issues with either of these sensors, the diagnostic scanner will show codes that could cause an engine shut down.

Some of the symptoms of a failed G28 sensor are an inaccurate rev counter in the gearbox and gears that shift faster than normal and/or misfiring when in gear. It is probable that your sensor is failing and needs to be replaced if you encounter any of these signs. The good thing is that they are very affordable and easy to find particularly if you're looking at a Bosch sensor, like ours. Alternatively, the GM version of this unit is also a great option.

5. Tachometer

A malfunctioning engine speed sensor could be a cause for numerous issues with your vehicle. It's a vital component of the audi replacement keys's transmission because it communicates to the ECU about how fast or slow the vehicle's crankshaft is turning. This sensor can cause the transmission to fail and other components of the car to be affected.

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 then processes the signal to control the flow of fuel, timig and boost and then transmitting it to the G5 Tachometer located in the instrument cluster. You can check for sensor failure by checking 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 [79trace [79]) and between pin T6a/1 as well as pin T26a/12. There should be the resistance to be around 1000 ohms between these two points. This is a common feature across the Audi Key replacement cost uk 80-100-200-RS2 model, ranging beginning with the 1985 MC and up to the 1997 UrS AN and the 1995 RS2 Du You may also find some good ones in wrecking yards.