How to Replace an new audi keys G28 Engine Speed Sensor
Charles the Humble Technician teaches how to replace the G28 Engine Speed Sensor. This sensor is located near the transmission's edge, above the flywheel gear. It transmits a signal to the ECU via a grey wire T55/49, then to the tachometer in the instrument cluster.
1. Engine Speed Sensor
The grey wire is situated on the edge of transmission, just above the flywheel ring. This sensor sends a signal via the grey wire to pin T55/49. The ECU utilizes this information to control boost and fuel. It also sends a signal to the G5 tachometer inside the instrument cluster.
The sensor is used as a reference point to connect with the G40 Camshaft Position Sensor. The ecu has to know when the crankshaft has reached TDC and also the position of the camshaft, so that it can activate the spark and injectors.
If this sensor fails when it fails, the ECU will display a P00160 error message. This indicates that the Crank Shaft is not in line with the Intake Camshaft. It could also indicate the possibility of a chain stretch or jump in the chain link of the upper timing chain. However, the code won't appear on its own, without additional information from other sensors (G4 and G40).
Testing is a bit tricky because there are two connector pins and they serve different purposes but the most effective method to test it is to measure resistance between the sensor and the ECU. When the sensor is operational, it should be reading around 1000 ohms. Examine for evidence of coolant or oil in the connector bay if there are problems with this part.
2. Injectors
Yesterday, while accelerating from the highway paytoll at full speed I noticed a massive decrease in power. It was like the engine had run out of gas. Or my injectors weren't firing. I took out the spark plugs this morning, three were drenched in gasoline and the fourth was unclean. I put tissue over each hole in the injector and when i turn the engine on without sparks, the ones with gazoline jump out. The fourth one remains closed. I tested the ground connection of ECU pins 14,30 and 48/55. I found zero ohm. I assume that 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 is running fine with the G28 plugged in. However, the intermittent misfire problem persists at higher RPM. The coolant sensor (G62) even when it is unplugged, shows a temperature of -49c. I also noticed that the oil gauge in the cockpit shows 2 bars but the actual pressure is zero.
I don't know what to do. I think I've all other possibilities out. But i am afraid I might have missed something. If anyone has any ideas please share them! TIA!
3. Fuel Pump
The fuel pump of the g28 receives a signal from the RPM sensor. The GM-style transmitter is similar to the G4 sender, and both operate on the 80,100,200, UrS, and RS2 vehicles. You can easily find an extra in a wrecking shop or parts store. It is simple to test them by putting your DMM in resistance mode and measure between pins 1 (with the bump on the connector's end up) and 2 (2nd from left on the black connector's side). They should be infinite ohms.
4. ECU
The ECU in our 20vt turbo (3B AAN ABY ADU) engines requires to know the speed and position of the crankshaft to determine timing of the fuel injector, etc. It uses a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If either of these go badly, you will see codes on the diagnostic scanner that can lead to engine shutdown.
Some of the signs of a malfunctioning G28 sensor include an inaccurate rev counter for the gearbox the gears are shifting faster than normal, and/or a misfire when in gear. If you experience any of these issues, it is likely that your sensor is failing and should be replaced. They're inexpensive and easy to locate, especially when they're an Bosch model like ours. Alternatively, GM's version of this part is a good option.
5. Tachometer
A faulty engine speed sensor could be the cause of many issues with your vehicle. It is a crucial part of the audi key fob replacement's transmission because it communicates to the ECU about how fast or slow the car's crankshaft is spinning. This sensor can cause the transmission to malfunction and other car components to be affected.
The G5 engine speed sensor is located on the outside of the transmission just above the flywheel ring gear and transmits a signal to the ECU at pin T55/49, via a grey wire. The ECU utilizes this signal to control fuel and boost, and also to timigrate. It also relays it to the G5 Tachometer located in the instrument cluster. You can test for sensor failure by checking continuity from the sensor to the tachometer. Also, 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 and pin T26a/12. There should be the resistance to be around 1000 ohms between these two points. This part is common across the audi tt key programming tt audi a4 key replacement audi key copy (informatic.wiki) 80-100-200-RS2 range, from the 1985 MC all the way up to the 1997 UrS An and 1995 RS2 DU, so you might find some good ones in wrecking yards.(Image: https://g28carkeys.co.uk/wp-content/uploads/2023/10/Porsche-New-2023.png)
