Audi G28: 10 Things I'd Like To Have Learned Earlier
Audi G28: 10 Things I'd Like To Have Learned Earlier
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How to Replace an Audi G28 Engine Speed Sensor
Charles the Humble Technician shows you how to replace the G28 Engine Speed Sensor. This sensor is situated on the outside of the transmission over the flywheel gear. It transmits a signal to the ECU via an uncolored wire T55/49, then to the tachometer 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 transmits signals through the grey wire to pin T55/49. The ECU utilizes this information to regulate the amount of fuel and boost. It also sends an indicator to the G5 Tachometer in instrument cluster.
The sensor is used to connect the G40 Camshaft position Sensor. The ecu must know when the crankshaft has reached TDC and also the position of the camshaft, to trigger the spark and injectors.
If this sensor fails, the ECU will display a P00160 error code. This indicates that the Crank Shaft is out of line with the Intake Camshaft. It could also indicate the possibility of a chain stretch or jump in the chain link of the upper chain. The code won't appear without the additional information provided by other sensors (G4 or G40).
It can be a bit difficult to test as there are several pins on the connector, and each one has different functions. The best method for doing this is to measure the resistance between the ECU and the sensor. It should read about 1000 ohms if the sensor is operating at its maximum. Examine for signs of coolant or oil in the connector bay if there are problems with this part.
2. Injectors
Yesterday, as i was accelerating off the highway paytoll at full speed I noticed a massive reduction 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 drenched in gasoline and the fourth was dry. When I start the engine with no sparks, I put a piece of tissue on the top of each hole in the injector, the 3 drenched with gazoline jump out but the 4th stay shut. I checked the ground connection of ECU pins 14,30 and 48/55. I got zero ohm. Therefore, i think the issue is in another place.
I also tried to reset PID without success. The car is able to start if the G28 is not plugged in and runs fine when it is plugged in but it still has the intermittent misfire issue at higher RPM. The coolant sensor (G62), even when unplugged, still shows an ice temperature of -49c. I also noticed that the oil pressure gauge in the cockpit is showing 2 bar when the actual pressure is 0.0 when i rev the engine.
I'm not sure what to do. I think I've eliminated everything else. However, i'm afraid that I may have missed something. If anyone has any suggestions, please let me know! TIA!
3. Fuel Pump
The fuel pump in the g28 receives signals from the RPM sensor. The GM-style transmitter is the same as the G4 and they both work in the 80 100, 200, UrS and RS2 cars which is why you can easily locate one at a junkyard or in a local parts store. It is easy to test them - just switch your DMM into resistance mode and determine the distance between check here pins 1 and 2 (with the bump on the connector's edge facing up). They must be infinite Ohms.
4. ECU
Our 20vt turbo (3B AAN, ABY, and ADU) engines have an ECU that must know the speed and position of the crankshaft to make a decision about fuel injector timing etc. To do this, it utilizes a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If you have a problem with either of these, the diagnostic scanner will show the codes that could trigger an engine shutdown.
A damaged G28 sensor could cause an inaccurate gearbox speed counter or a gearbox that shifts more replacement key for audi a3 quickly than normal, or a misfire in the gear. It is possible that your sensor is failing and needs to website be replaced if you notice any of these symptoms. The good news is that they are very cheap and easily accessible, especially if you're looking at a Bosch sensor, like ours. Alternatively, the GM version of this part is also a good choice.
5. Tachometer
A malfunctioning engine speed sensor could be the reason behind numerous issues in your car. It is a crucial part of the Audi's transmission since it relays get more info information to the ECU about how the car's crankshaft is turning. When this sensor fails, it will 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 to the ECU at read more pin T55/49, via a grey wire. 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 failure by examining the continuity between it and the tachometer, between the ECU pin T55/49 and the instrument cluster connection to pin T6a/1 (trace [79trace [79]) and between pin T6a/1 and the instrument cluster pin T26a/12. It should show approximately 1000 ohms of resistance between those points. This is a standard component across the Audi 80, 100, 200, UrS and RS2 range from 1985 MC through the 1997 UrS AAN and 1995 RS2 ADU. Good ones might be availble in wrecking yards.