How to Replace an Audi G28 Engine Speed Sensor
Charles the Humble Technician teaches you how to replace the G28 Engine Speed Sensor. This sensor is situated near the transmission's edge just above the flywheel gear. It sends a message to the ECU via a grey wire T55/49, then to the tachometer on 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 transmits signals through the grey wire to pin T55/49. The ECU uses this information to control fuel and boost. It also sends an indicator to the G5 Tachometer within the instrument cluster.
The sensor is used to correlate with the G40 Camshaft position Sensor. The ecu must be aware of when the crankshaft has reached TDC and also the position of the camshaft, in order to activate the spark and injectors.
If this sensor fails, the ECU will display a P00160 error message. This indicates that the Crank Shaft is not in sync with the Intake Camshaft. It could also indicate a chain stretch or a jumped chain link in the upper chain. The code will not appear without the additional information provided by other sensors (G4 or G40).
Testing is a bit challenging because there are two pins for the connector and they serve different purposes but the best method of testing it is by measuring resistance between the sensor and the ECU. When the sensor is fully operational, it should read approximately 1000 ohms. If you are having problems with this component, look for evidence of oil or coolant in the connector bay.
2. Injectors
Yesterday, when i was accelerating to the fullest speed from highway paytoll i had an abrupt drop in power like the engine is running out of gas or injectors are not firing at all. I took out the spark plugs this morning and found that 3 were soaked in gasoline, and the 4th was dry. When i crank the engine with no sparks, i place a tissue on the top of each of the injector holes and the 3 drenched with gazoline leap out, however the 4th stay closed. I checked the ground connection of ECU pins 14,30 and 48/55. I found 0ohm. I'm assuming the issue is somewhere else.
I also tried to reset PID but without success. The car will start when the G28 is disconnected, but it is running fine with the G28 connected. However the intermittent misfire issue still occurs at higher RPM. The temperature sensor for coolant (G62) shows the wrong temperature value of -49c, even if I unplug it. I also noticed that the oil gauge in the cockpit shows 2 bar when the actual pressure is 0.
I'm not certain what to do, but i feel i have pretty much eliminated everything else. However, i'm afraid that i might have missed something. If anyone has any suggestions, please chime in! TIA!
3. Fuel Pump
The fuel pump in the g28 can be activated by a signal sent 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. It is easy to find a spare in a wrecking shop or a parts store. Testing them is easy 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 connector's side). They should be infinite Ohms.
4. ECU
The ECU of our 20vt turbo (3B AAN ABY) engines requires to know the speed and position of the crankshaft to determine timing of the fuel injector, etc. It makes use of a Crank Position Sensor audi a3 replacement key G4 and an Engine Speed Sensor G28 to achieve this. If you have a problem with either of these sensors, the diagnostic scanner will show codes that could cause an engine shutdown.
Some of the symptoms of a failing G28 sensor are an inaccurate rev counter for the gearbox and gears that shift faster than normal and/or misfiring when in gear. If you are experiencing any of these issues, it is most likely that your sensor is failing and needs replacing. They are cheap and easy-to-find replacement audi key particularly when they're a Bosch unit like ours. Alternately, GM's version this component is an excellent choice.
5. Tachometer
A damaged engine sensor could cause a myriad of issues in your car. It's an essential component of the transmission in your Audi since it sends information to the ECU about how fast or slowly the engine is turning. This sensor could cause the transmission to malfunction and other car components to be affected.
The G5 engine sensor is located at the edge of the transmission, just above the flywheel ring. It transmits a signal via gray wire to ECU pin T55/49. The ECU is then able audi key replacement near me to process this signal to control fuel, timig, and boost as well as transmitting it replacement car key audi to the G5 tachometer in the instrument cluster. You can test the sensor for failure by checking continuity between it and the tachometer, between ECU pin T55/49 and the instrument cluster connection via pin T6a/1 (trace [79]) as well as between T6a/1, and the instrument cluster pin T26a/12. You should see approximately 1000 ohms resistance between these two points. This is a typical part across the Audi 80, 100 200, lost audi keys UrS and RS2 range from 1985 MC through the 1997 UrS AAN and 1995 RS2 ADU. Good ones might be availble in wrecking yards.