How to Replace an programming audi key G28 Engine Speed Sensor

In this video, Charles the Humble Mechanic demonstrates how to replace the G28 engine speed sensor. This sensor is located at the edge of transmission, above the flywheel gear. It transmits a signal to the ECU via the grey wire T55/49 and then to the tachometer on the instrument cluster.

1. Engine Speed Sensor

The grey wire is situated at the edges of the transmission, new audi key tt key programming; https://telegra.ph, above the flywheel ring. The sensor transmits signals through the grey wire to pin T55/49. The ECU uses this information to control the amount of fuel and boost. It also sends an indication to the G5 tachometer in the instrument cluster.

The sensor is used to correlate the G40 Camshaft position Sensor. The ecu must know when the crankshaft is TDC and the location of the camshaft so it can start spark and injectors in the right way.

If this sensor fails, the ECU will display the P00160 error, which means the Crank Shaft and Intake Camshaft aren't in sync and possibly indicating the chain stretching or a jump link on the upper chain of timing. However, the code won't appear on its own without additional information from other sensors (G4 and G40).

Testing can be a bit difficult since there are two connector pins, and they have different functions but the most effective method of testing it is to measure the resistance between the sensor and the ECU. When the sensor is operational, it should read about 1000 ohms. Look for signs of coolant or oil in the connector bay if you have issues with this component.

2. Injectors

Yesterday, when accelerating from highway paytoll at full speed I noticed a massive decrease in power. It was as if the engine was running out of gas. Or my injectors were not firing. I took out the spark plugs this morning, three were soaked in gasoline, and the fourth was dry. I put tissue over each injector hole, and when I start the engine with no sparks, the ones with gazoline jump out. The 4th one remains shut. I tried to test the ground connections of ECU pins 14,30, and 48/55. I got 0ohm. I assume that the problem is in another location.

I also tried to reset PID but without success. The car will start if the G28 is disconnected and runs fine when it is plugged in however it has the intermittent misfire issue at higher RPM. The coolant sensor (G62), even if it is not plugged in, shows temperatures of -49c. 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, but i feel i have pretty much ruled out everything else. However, i'm afraid that I might have missed something. If anyone has suggestions, please share them! TIA!

3. Fuel Pump

The fuel pump of the g28 gets a signal from the RPM sensor. The GM-style transmitter is similar to the G4 sender and both work 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 simple to test them: simply switch 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 ADU) engines requires to know both the position and speed the crankshaft in order to make a decision about fuel injector timing, etc. In order to do this it uses a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If either of these sensors go wrong, you will receive codes on the diagnostic scanner which could cause engine shut down.

A damaged G28 sensor could result in an inaccurate gearbox speed counter, a gearbox that shifts faster than normal, and/or an unfire when in the gear. If you are experiencing any of these issues, it is most likely that your sensor is failing and requires replacement. The good thing is that they are very affordable and easily accessible particularly if you're looking at an Bosch model, which is what we have. Alternately, GM's version this component is a good option.

5. Tachometer

A failing engine speed sensor could be the reason behind many issues in your vehicle. It's an essential component of your audi q7 key's transmission, since it relays information to the ECU about how the car's crankshaft is spinning. If this sensor fails, it will disrupt the performance of the transmission, as well as the other car's components.

The G5 engine sensor is located near the edge of transmission, above the flywheel ring. It transmits signals via gray wire to ECU pin T55/49. The ECU then uses and processes this signal to control fuel, timig, and boost, and also transmitting it to the G5 Tachometer located 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 [79trace [79]) and between pin T6a/1 and the instrument cluster pin T26a/12. It should show around 1000 ohms of resistance between these two points. This is a common feature across the audi tt key fob 80-100-200-RS2 series, Audi a1 key starting from the 1985 MC up to the 1997 UrS AN and 1995 RS2 DU, so you might find good ones in wrecking yards.