How to Replace an audi replacement key cost G28 Engine Speed Sensor

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

1. Engine Speed Sensor

The grey wire is situated at the edges of the transmission, above the flywheel ring. The sensor transmits signals through the grey wire to pin T55/49. The ECU then uses this information to control the flow of fuel, timig and [Redirect Only] boost. It also sends an alert to the G5 Tachometer within 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 according to the situation.

If this sensor fails, the ECU will display the P00160 error, which means the Crank Shaft and Intake Camshaft are out of sync, possibly indicating the chain is stretched or a jump link on the upper timing chain. The code will not appear without the additional information supplied by other sensors (G4 or G40).

It can be a bit difficult to test since there are various pins on the connector and each has its own functions. The best way to do it is to measure the resistance between the ECU and the sensor. If the sensor is operational, it should be reading approximately 1000 ohms. If you're having issues with this part, check for signs of coolant or oil in the connector bay.

2. Injectors

Yesterday, as i was accelerating off the highway paytoll at a high speed, i noticed a huge drop in power. It was as if the engine had run out of gas. Or my injectors were not firing. I took out the spark plugs this morning, 3 were soaked in gasoline, and the fourth was dry. I put tissue over each injector hole, and when i turn the engine on without sparks, audi key copy the ones with gazoline jump 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. I assume that the problem is elsewhere.

I also tried to reset the PID but with no luck. The car will start when the G28 is unplugged, and it runs fine with the G28 connected. However the intermittent misfire issue persists at higher RPM. The coolant sensor (G62) even when it is unplugged, shows temperatures 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'm not sure what to do. I feel like i've pretty much eliminated everything else. However, i'm afraid that I might have missed something. If anyone has any ideas please chime in! TIA!

3. Fuel Pump

The fuel pump on the g28 is activated by a signal sent by the RPM sensor. The GM-style sensor is the same as the G4 and both function in the 80, 100 200, UrS and RS2 cars which is why you can easily locate one at a wrecking yard or at a parts store. It is easy to test them: simply put your DMM into resistance mode and determine the distance between pins 1 and 2 (with the bump on the connector's edge facing up). They should be infinite Ohms.

4. ECU

The ECU of our 20vt turbo (3B AAN ABY) engines needs to be aware of the speed and position of the crankshaft in order to make a decision about fuel injector timing, etc. It utilizes a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If either of these goes wrong, you will receive codes on the diagnostic scanner that can lead to engine shutdown.

A malfunctioning G28 sensor could cause an inaccurate gearbox speed counter, a gearbox that shifts faster than normal, or an unfire when in the gear. It is possible that your sensor is failing and needs to be replaced if you experience any of these symptoms. They are cheap and easy-to-find particularly when they're a Bosch unit like ours. Alternately, GM's version this part is an option.

5. Tachometer

A damaged engine sensor could cause a variety of issues in your vehicle. It is an important part of the transmission in your audi key replacement because it relays information to the ECU regarding how fast or slowly the engine of the car is spinning. If this sensor fails, it could disrupt the performance of the transmission and the other car's components.

The G5 engine sensor is located near the edge of the transmission, just above the flywheel ring. It sends an electrical signal through gray wire to ECU pin T55/49. The ECU then uses and processes this signal to control the flow of fuel, timig and boost and then transmitting it to the G5 tachometer in the instrument cluster. You can determine if the sensor is in failure by checking continuity from the sensor to the tachometer. Also, you can check continuity between pin T55/49 of the ECU and pin T6a/1 of the instrument cluster (trace [79]), and between pin T6a/1 and pin T26a/12. You should see the resistance to be around 1000 ohms between these two points. This is a common feature across the audi car key case 80-100-200-RS2 model, ranging from the 1985 MC all the way up to the 1997 UrS An and 1995 RS2 Du You may also find some good ones in wrecking yards.