How to Replace an audi a4 key replacement G28 Engine Speed Sensor
Charles the Humble Technician shows how to replace the G28 Engine Speed Sensor. This sensor is located near the edges of the transmission above the flywheel ring gear. It sends a signal to the ECU via a grey wire (T55/49), cost of audi key Replacement then to the tachometer located in the instrument cluster.
1. Engine Speed Sensor
The grey wire is located at the edges of the transmission, just above the flywheel ring. The sensor sends an electrical signal through the grey wire to pin T55/49. The ECU utilizes this information to control boost and fuel. It also sends an alert to the G5 Tachometer in instrument cluster.
The sensor serves as a reference for comparing with the G40 Camshaft Position Sensor. The ecu has to know when the crankshaft has reached TDC and also the location of the camshaft so that it can activate the spark and injectors.
If this sensor fails the ECU will show an error code P00160 which indicates that the Crank Shaft and Intake Camshaft are out of sync, possibly indicating chain stretch or a jumped link on the upper timing chain. The code will not appear without the additional information provided by other sensors (G4 or G40).
Testing can be a bit difficult since there are two pins for the connector and they serve different purposes however the best method to test it is to measure the resistance between the sensor and the ECU. It should read approximately 1000 ohms when it is operating at its maximum. Look replacement key for audi a4 signs of coolant or oil in the connector bay if you are experiencing issues with this part.
2. Injectors
Yesterday accelerating full speed from highway paytoll, i experienced massive power loss as if the engine was running out of gas or injectors are not firing any more. I pulled out the spark plugs this morning, 3 were soaked in gasoline, and the 4th was dry. I placed a tissue over each hole in the injector and when i start the engine without sparks, the ones with gazoline jump right out. The fourth one remains shut. I checked the ground connection of ECU pins 14,30, and 48/55. I got zero ohm. I'm assuming that the issue is in another location.
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 connected. However, the intermittent misfire problem still occurs at higher RPM. The coolant sensor (G62) even when unplugged, still shows an ice temperature of -49c. I also noticed that the oil gauge in the cockpit shows 2 bar but the actual pressure is 0.
I'm not certain what to do, as i think i've pretty much eliminated everything else. I'm concerned that i may have missed something. Please let me know If you have any suggestions! TIA!
3. Fuel Pump
The fuel pump in the g28 receives a signal from the RPM sensor. The GM-style sender is the same as the G4 and both are used in the 80, 100 200, UrS and RS2 cars which is why you can easily locate one at a junkyard or from a parts store. It is easy to test them - just put your DMM into resistance mode and determine 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 of our 20vt turbo (3B AAN ABY ADU) engines must know both the position and speed of the crankshaft in order to make a decision about timing of fuel injectors, etc. To accomplish this, it uses a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If you have a problem with either one of these, the diagnostic scanner will display the codes that could trigger an engine shut down.
A damaged G28 sensor can cause an inaccurate speed counter for the gearbox and a gearbox which shifts more quickly than normal, or an unfire when in gear. It is probable that the sensor is failing and needs to be replaced if you experience any of these signs. The good news is they are very affordable and easily accessible, especially when you're looking at the Bosch sensor, which is what we have. Alternatively, GM's version of this part would be a good option.
5. Tachometer
A malfunctioning engine speed sensor could be the cause of a slew of issues in your car. It's a crucial component of the transmission in your audi tt key fob since it sends information to the ECU about how fast or slowly the engine of the car is turning. If this sensor fails, it will cause problems for the transmission, as well as the rest of the car's components.
(Image: https://g28carkeys.co.uk/wp-content/uploads/2023/10/holding-car-keys-woman-in-formal-clothes-is-indoo-2021-12-27-15-52-03-utc-min-scaled.jpg)The G5 engine sensor is located at the outskirts of the transmission, over the flywheel ring. It transmits a signal via gray wire to ECU pin T55/49. The ECU then uses and processes the signal to control the flow of fuel, timig and boost as well as transmitting it to the G5 Tachometer located in the instrument cluster. You can test the sensor for failure by checking continuity between it and Replacement Audi Key Cost the tachometer, between the ECU pin T55/49 and the instrument cluster connection via pin T6a/1 (trace [79]) and between T6a/1 and the instrument cluster pin T26a/12. You should see approximately 1000 ohms of resistance between these two points. This is a standard part across the Audi Replacement Key Service Near Me 80, 100, 200, UrS and RS2 range from 1985 MC to the 1997 UrS AAN and 1995 RS2 ADU. Good parts could be found in wrecking yards.
