How to Replace an audi key replacement cost uk G28 Engine Speed Sensor
Charles the Humble Technician shows you how to replace the G28 Engine Speed Sensor. This sensor is located at the edge of transmission, above the flywheel gear. It sends a signal to the ECU via the grey wire (T55/49) which is then sent to the tachometer located in the instrument cluster.
1. Engine Speed Sensor
The grey wire is located at the edges of the transmission, directly above the flywheel ring. The sensor transmits an electrical signal through the grey wire to pin T55/49. The ECU then utilizes this information to regulate the flow of fuel, timig and boost. It also sends signals to the G5 tachometer inside the instrument cluster.
The sensor is used as a reference to correlate with the G40 Camshaft Position Sensor. The ecu needs to know when the crankshaft has reached TDC, and the location of the camshaft in order to activate the spark and injectors.
If this sensor fails the ECU will display the P00160 error, which means the Crank Shaft and Intake Camshaft are not in sync and could indicate the chain is stretched or a jump link on the upper chain of timing. The code will not appear without the additional information provided by other sensors (G4 or G40).
It is a little tricky to test as there are different pins on the connector and each has its own functions. The best method for doing this is by measuring the resistance between the ECU and the sensor. It should read around 1000 ohms when the sensor is in full operation. If you're having issues with this sensor, look for evidence of coolant or oil in the connector bay.
2. Injectors
Yesterday, as i was accelerating off the highway paytoll at full speed I noticed a massive drop in power. It was as if the engine had run out of gas. Or, my injectors weren't firing. I took out the spark plugs this morning, three were soaked with gasoline and the 4th was dry. When I start the engine with no sparks i put tissue on top of each injector hole and the 3 drenched with gazoline pop out, but the 4th one stays shut. I checked the ground connection of ECU pins 14,30, and 48/55. I got zero ohm. I'm assuming the issue is somewhere else.
I also tried to reset the PID with no success. The car is able to start when the G28 is not plugged in and is running fine when it is plugged in, audi car key case but still has intermittent misfire issues at higher RPM. The coolant sensor (G62) even if it is not plugged in, shows temperatures of -49c. Also i noticed that the gauge for oil pressure in the cockpit is showing 2 bar while the actual pressure is 0.0 when I crank up the engine.
I'm not certain what to do, as i believe that i've 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 in the g28 is activated by a signal by 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 a spare in a wrecking shop or a parts store. It is simple to test them - simply put your DMM into resistance mode and test the distance between pins 1 and 2 (with the bump at the connector end facing upwards). They must be infinite Ohms.
4. ECU
The ECU in our 20vt turbo (3B AAN ABY ADU) engines needs to be aware of the speed and position of the crankshaft to make decisions regarding timing of the fuel injector, etc. It uses a Crank Position Sensor G4 and an Engine Speed Sensor G28 to achieve this. If either of these goes bad you will get codes on the diagnostic scanner which can lead to engine shutdown.
A damaged G28 sensor could result in an inaccurate gearbox speed counter or a gearbox that shifts faster than normal, or an unfire when in gear. If you have any of these issues it is most likely that your sensor is failing and should be replaced. They're inexpensive and easy to locate particularly in the case of a Bosch model like ours. Alternatively, the GM version of this unit is also a great option.
5. Tachometer
A failing engine speed sensor could be the cause of many issues with your vehicle. It's an essential component of your audi replacement key cost's transmission, as it sends information to the ECU about how fast or slow the vehicle's crankshaft is spinning. When this sensor fails, it could affect the performance of the transmission and the other car's components.
The G5 engine speed sensor is located at the edge of the transmission above the flywheel ring gear. It sends a signal directly to the ECU at pin T55/49, via a grey wire. The ECU is then able to process the signal to control fuel, timig, and boost as well as transmitting it to the G5 tachometer in the instrument cluster. You can test for sensor failure by examining the continuity from the sensor to the tachometer. Also, you can verify continuity between pin T55/49 of the ECU and pin T6a/1 of the instrument cluster (trace [79trace [79]) and between pin T6a/1 and pin T26a/12. You should observe approximately 1000 ohms resistance between those two pins. This is a standard part across the replacement audi a3 key 80, 100 200, UrS and RS2 range from 1985 MC through the 1997 UrS AAN and 1995 RS2 ADU so good parts could be found in wrecking yards.