How to Replace an replacement audi key fob 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 just above the flywheel gear. It transmits a signal to the ECU via an uncolored wire T55/49, then to the tachometer located on the instrument cluster.
1. Engine Speed Sensor
Located on the edge of the transmission above the flywheel ring gear G28 Engine Speed Sensor sends a signal to ECU pin T55/49 via the grey wire. The ECU uses this information to control the amount of fuel and boost. It also sends an indication to the G5 Tachometer located in the instrument cluster.
The sensor is used to connect the G40 Camshaft position Sensor. The ecu has to be aware of when the crankshaft has reached TDC, and where the camshaft lies to trigger the spark and injectors.
If this sensor fails the ECU will display 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. However, the code won't appear on its own without additional information from other sensors (G4 and G40).
Testing can be a bit difficult because there are two connector pins, and they perform different functions but the most effective way to test it is to measure the resistance between the sensor and the ECU. When the sensor is fully operational, it should be reading around 1000 ohms. Check for signs of coolant or oil in the connector bay if you have issues with this part.
2. Injectors
Yesterday, when accelerating from highway paytoll at a high speed, i noticed a huge reduction in power. It was like the engine had run out of gas. Or, my injectors were not firing. Today, i pulled out the spark plugs. Three were drenched with gazoline the 4th one was dry. When I start the engine without sparks, I put a piece of tissue on the top of each hole in the injector and the 3 drenched with gazoline pop out, but the 4th one stays closed. I checked the ground connection on ECU pins 14/55, 30/55 and 48/55. I got 0ohm. I'm assuming that the issue is somewhere else.
I also tried to reset the PID 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 still occurs at higher RPM. The temperature sensor for coolant (G62) shows the wrong temperature of -49c, audikey (please click the following website) even if I unplug it. Also, i noticed that the oil pressure gauge in the cockpit is showing 2 bar, whereas the actual pressure is 0.0 when I crank up the engine.
I'm not sure what to do, as i believe that i've completely ruled out all other possibilities. I'm concerned that i may have missed something. Let me know should you have any suggestions! TIA!
3. Fuel Pump
The fuel pump in the g28 is activated by a signal sent by 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 locate a spare in a wrecking shop or a parts store. Test them out by putting your DMM in resistance mode and measure between pins 1 (with the bump on the connector's side up) and 2 (2nd from the 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 know the position and speed of the crankshaft in order to make a decision about timing of the fuel injector, etc. It utilizes a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If either of these goes bad you will get codes on the diagnostic scanner that could cause engine shut down.
A failing G28 sensor could cause an inaccurate gearbox speed counter or a gearbox that shifts more quickly than normal, and/or a misfire while in gear. If you have any of these issues it is most likely that your sensor is failing and requires replacement audi key. They are cheap and easy-to-find especially if they're a Bosch sensor like ours. Alternately, the GM version of this part is also a great option.
5. Tachometer
A malfunctioning engine speed sensor could be the reason behind a slew of issues in your vehicle. It's a vital component of your Audi's transmission, as it sends information to the ECU about how fast or slow the car's crankshaft is turning. This sensor could cause the transmission to fail and other components of the car to be affected.
The G5 engine speed sensor is located on the outside of the transmission, above the flywheel ring gear. It sends a signal directly to the ECU at pin T55/49 via an uncolored wire. The ECU utilizes this signal to control fuel and boost, as well as timig. It also sends it to the G5 Tachometer located in the instrument cluster. You can test for sensor failure by examining the 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 [79]) and between pin T6a/1 and pin T26a/12. You should observe approximately 1000 ohms of resistance between those points. This is a standard part that is found across the audi key replacement cost uk 80, 100, 200, UrS and RS2 range from 1985 MC until the 1997 UrS AAN and 1995 RS2 ADU. Good parts could be found in wrecking yards.