20 Myths About Audi G28: Dispelled
20 Myths About Audi G28: Dispelled
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How to Replace an Audi G28 Engine Speed Sensor
In this video, Charles the humble mechanic demonstrates how to replace the G28 engine speed sensor. This sensor is located near the transmission's edge, above the flywheel gear. It sends a signal to the ECU via the grey wire (T55/49) which is then sent to the tachometer within the instrument cluster.
1. Engine Speed Sensor
Located on the edge of the transmission above the flywheel ring gear, the G28 Engine Speed Sensor sends an electrical signal to ECU pin T55/49 via the grey wire. The ECU then utilizes this information to regulate fuel, timig and boost. It also sends a signal to the G5 tachometer in the instrument cluster.
The sensor serves as a reference to correlate with the G40 Camshaft Position Sensor. The ecu must know when the crankshaft is TDC and the location of the camshaft so it can start spark and injectors according to the situation.
If this sensor fails to function, the ECU will display an error code P00160. This means that the Crank Shaft is not in alignment with the Intake Camshaft. It could also indicate a chain stretch or a jumped chain link in the upper chain of timing. The code won't show without the additional information supplied by other sensors (G4 or G40).
Testing is a bit tricky because there are two pins for the connector and they have different functions however the best method of testing it is to measure resistance between the sensor and the ECU. It should read about 1000 ohms when the sensor is in full operation. Look for signs of coolant or oil in the connector bay if there are problems with this part.
2. Injectors
Yesterday, while accelerating from the highway paytoll at maximum speed, i noticed a huge decrease in power. It was like the engine was running out of gas. Or my injectors weren't firing. I pulled out the spark plugs this morning, three were soaked in gasoline, and the fourth was dry. I placed a tissue over each injector hole, and when I start the engine with no sparks, the ones with gazoline jump out. The fourth one remains shut. I inspected the ground connection on ECU pins 14/55/30/55/48/55/14/55/48/ I get 0ohm. I'm assuming that the issue is somewhere else.
I also tried to reset PID without success. The car can start when the G28 is unplugged and it runs perfectly when it is plugged in, but still is experiencing intermittent misfires at higher RPM. The coolant temperature sensor (G62) shows the wrong temp value -49c, even if I unplug it. Also i noticed that the gauge for oil pressure in the cockpit shows 2 bar while the actual pressure is 0.0 when i rev the engine.
I'm not sure what to do. I feel like i've pretty much eliminated everything else. But i'm worried that i might have missed something. Let me know If you have any suggestions! TIA!
3. Fuel Pump
The fuel pump in the g28 is activated by a signal from 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 find the spare in a salvage shop or a parts store. Testing them is easy by putting your DMM in resistance mode and measure the resistance between pins 1 (with the bump on the connector's side up) and 2 (2nd from the left on the black connector's end). They must be infinite Ohms.
4. ECU
The ECU in our 20vt turbo (3B AAN ABY ADU) engines needs to know both the position and speed of the crankshaft to determine timing of the fuel injector, etc. To accomplish this, it utilizes a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If you encounter a problem with either of these sensors, the diagnostic scanner will show the codes that could trigger an engine shut down.
Some audi key programming near me of the symptoms of a failing G28 sensor are an inaccurate rev counter for the gearbox the gears are shifting faster than normal and/or misfiring when you're in gear. It is probable that your sensor is failing and requires to be replaced if you notice any of these symptoms. The good news is they are very affordable and easy to find, especially when you're looking at an Bosch sensor, which is what we have. Alternately, the GM version of this part is also a good choice.
5. Tachometer
A damaged engine sensor could cause a variety of issues in your vehicle. It's an essential component of the transmission read more in your Audi since it sends information to the ECU about how fast or slowly the engine is spinning. This sensor can cause the transmission to fail and other components of the car to be affected.
The G5 engine sensor is located at the outskirts of transmission, above the flywheel ring. click here It transmits a signal via an uncolored wire to the ECU pin T55/49. The ECU utilizes this signal to control click here the flow of fuel and boost and also to timigrate. It also sends it to the G5 Tachometer located in 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 on pin T6a/1 click here (trace [79]) as well as between T6a/1, and the instrument cluster pin T26a/12. It should show around 1000 ohms of resistance between those two pins. This is a standard part that is found across the Audi 80 100 200, UrS and RS2 range from 1985 MC until the 1997 UrS AAN and 1995 RS2 ADU. Good ones might be availble in wrecking yards.