How to Replace an Audi car Key holder G28 Engine Speed Sensor

Charles the Humble Technician shows you how to replace the G28 Engine Speed Sensor. The sensor is located near the edges of the transmission, above the flywheel ring gear. It sends a signal to the ECU via the grey wire (T55/49), then to the tachometer within the instrument cluster.

1. Engine Speed Sensor

The grey wire is situated on the edge of transmission, directly above the flywheel ring. The sensor transmits an electrical signal through the grey wire to pin T55/49. The ECU utilizes this information to control fuel and boost. It also sends an indication to the G5 Tachometer within the instrument cluster.

The sensor is used to link 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 according to the situation.

If this sensor fails the ECU will show an error code P00160 which indicates that the Crank Shaft and Intake Camshaft are out of sync and could indicate chain stretch or a jumped link on the upper timing chain. The code will not appear without the additional information provided by other sensors (G4 or G40).

It's a bit tricky to test as there are different connector pins, and they all have different functions. The most effective method to test it is to measure the resistance between the ECU and the sensor. When the sensor is fully operational, it should be reading around 1000 ohms. If you're experiencing issues with this part, check for evidence of coolant or oil in the connector bay.

2. Injectors

Yesterday, when i was accelerating to the fullest speed from highway paytoll, i experienced massive power loss as if the engine was running out of gas or the injectors are not firing at all. I took out the spark plugs this morning and found that 3 were drenched in gasoline and the fourth was unclean. I put a piece of tissue over each hole in the injector and when i start the engine without sparks, the three with gazoline jump right out. The 4th one stays shut. I inspected the ground connection on ECU pins 14/55,30/55 and 48/55 i get zero Ohm. So i assume the problem is elsewhere.

I also tried to reset the PID but without success. The car will start when the G28 is unplugged, and it works fine when the G28 plugged in. However the intermittent misfire issue still occurs at higher RPM. The temperature sensor for coolant (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 when the actual pressure is 0.

I'm not certain what to do, but i feel i have pretty much eliminated everything else. I'm concerned that i may have missed something. Let me know If you have any suggestions! TIA!

3. Fuel Pump

The fuel pump in the g28 gets a signal from the RPM sensor. The GM-style sensor is identical to the G4 and New audi keys they both work in the 80, 100, 200, UrS and RS2 cars which is why you can easily locate one at a salvage yard or in a local parts store. It is simple to test them - just switch your DMM into resistance mode and determine the distance between pins 1 and 2 (with the bump at the connector's end facing upwards). They should be infinite Ohms.

4. ECU

The ECU of our 20vt turbo (3B AAN ABY) engines requires to know the position and speed of the crankshaft to determine fuel injector timing, etc. It makes use of a Crank Position Sensor G4 and an Engine Speed Sensor G28 to achieve this. If you have a problem with either of these sensors, the diagnostic scanner will show codes that could cause an engine shutdown.

Some of the signs of a malfunctioning G28 sensor are an inaccurate rev counter in the gearbox, gears shifting quicker than normal, and/or a misfire when you're in gear. It is possible that your sensor is failing and requires to be replaced if you notice any of these signs. They're cheap and easy to find especially when they're a Bosch model like ours. Alternately, GM's version this part is a good option.

5. Tachometer

A damaged engine sensor could cause a variety of issues in your vehicle. It's an essential component of the audi tt key fob's transmission since it relays information to the ECU about how fast or slow the vehicle's crankshaft is turning. This sensor can cause the transmission to malfunction and other components in 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 gray wire to ECU pin T55/49. The ECU is then able to process the signal to control fuel, timig and boost as well as sends it on to the G5 tachometer in the instrument cluster. You can test the sensor for failure by examining the continuity between it and the tachometer, between ECU pin T55/49 and the instrument cluster connection via pin T6a/1 (trace [79]) and between T6a/1 and the instrument cluster 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 car keys replacement 80-100-200-RS2 range, from the 1985 MC up to the 1997 UrS AN and 1995 RS2 Du You may also find them in wrecking yards.