How to Replace an Audi G28 Engine Speed Sensor
Charles the Humble Technician shows you how to replace the G28 Engine Speed Sensor. The sensor is situated on the edge of the transmission above the flywheel ring gear. It sends a message to the ECU through the grey wire T55/49 and then to the tachometer in the instrument cluster.
1. Engine Speed Sensor
It is located on the outside of the transmission just above the flywheel ring gear, the G28 Engine Speed Sensor sends an electrical signal to ECU pin T55/49 through an uncolored wire. The ECU then utilizes this information to regulate the boost, fuel, and timig. It also sends an indication to the G5 Tachometer within the instrument cluster.
The sensor is used to connect the G40 Camshaft position Sensor. The ecu needs to know when the crankshaft is TDC and where the camshaft is so it can activate spark and injectors according to the situation.
If this sensor fails when it fails, the ECU will display a P00160 error message. This means that the Crank Shaft is out of line with the Intake Camshaft. It could also indicate a chain stretch or a jumpy chain link in the upper timing chain. The code will not appear without the additional information supplied by other sensors (G4 or G40).
Testing can be a bit difficult since there are two connector pins and they have different functions however the best way to test it is to measure resistance between the sensor and the ECU. When the sensor is fully functional, it should read approximately 1000 ohms. If you are having problems with this part, check for evidence of coolant or oil in the connector bay.
2. Injectors
Yesterday, as i was accelerating off the highway paytoll at maximum speed, i noticed a huge drop in power. It was as if the engine was running out of gas. Or, my injectors were not firing. I pulled out the spark plugs this morning, 3 were soaked in gasoline, and the fourth was dry. When I start the engine with no sparks i put tissue on the top of each of the injector holes and the 3 drenched with gazoline jump out but the 4th stay closed. I tried to test the ground connections of ECU pins 14,30 and 48/55. I got 0ohm. So i assume the problem is somewhere else.
I also tried to reset PID without success. The car is able to start when the G28 is disconnected and is running fine when it is connected however it has intermittent misfire issues at higher RPM. The coolant sensor (G62) even if it is not plugged in, shows a temperature 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 audi car key replacement certain what to do, but i think i've pretty much ruled out everything else. But i'm worried that I might have missed something. If anyone has suggestions, please share them! TIA!
3. Fuel Pump
The fuel pump of the g28 gets a signal from 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 an extra in check here a wrecking shop or parts store. It is simple to test them to do - new audi key just put your DMM in resistance mode and measure the resistance between pins 1 (with the bump on the connector's end up) and 2 (2nd from left on the black end of the connector). They must be infinite Ohms.
4. ECU
The ECU of our 20vt turbo (3B AAN ABY ADU) engines requires to be aware of new audi key the speed and position of the crankshaft to make decisions regarding fuel injector timing, etc. To accomplish this, it utilizes a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If either of these go wrong, you will receive codes on the diagnostic scanner which can lead to engine shutdown.
Some of the signs of a failing G28 sensor are an inaccurate rev counter in the gearbox the gears are shifting faster than normal and/or misfiring when you are in gear. If you have any of these problems, it is most likely that your sensor is going bad and requires replacement. They are cheap and easy-to-find, especially if they're an Bosch model like ours. You can also choose the GM version of this unit is also a good option.
5. Tachometer
A failing engine sensor could cause a number of problems in your vehicle. It is an important part of the transmission of your Audi because it relays information to the ECU about how fast or slow the engine is spinning. If the sensor fails, it could affect the performance of the transmission and the other car's components.
The G5 engine sensor is located at the outskirts of transmission, above the flywheel ring. It transmits an electrical signal through a gray wire to the ECU pin T55/49. The ECU then uses and processes the signal to control the flow of fuel, timig and boost and then sends it on to the G5 tachometer inside the instrument cluster. You can test the sensor for any failure by checking the continuity between it and the tachometer, between the ECU pin T55/49 and the instrument cluster connection to pin T6a/1 (trace [79]) and between T6a/1 and the instrument cluster pin T26a/12. You should see approximately 1000 ohms resistance between those points. This is the same across the Audi 80-100-200-RS2 model, ranging beginning with the 1985 MC and up to the 1997 UrS An audi car keys replacement and 1995 RS2 DU So, you may find them in wrecking yards.