Ten Things You Need To Be Aware Of Audi G28
Ten Things You Need To Be Aware Of Audi G28
Blog Article
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 located near the edges of the transmission above the flywheel ring gear. It sends a message to the ECU via a grey wire T55/49, then to the tachometer located on 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 a signal to ECU pin T55/49 using the grey wire. The ECU uses this information to regulate boost and fuel. It also sends a signal to the G5 tachometer inside the instrument cluster.
The sensor is used as a reference for comparing with the G40 Camshaft Position Sensor. The ecu must be aware when the crankshaft is TDC and the location of the camshaft so it can activate spark and injectors accordingly.
If this sensor fails when it fails, the ECU will display a P00160 error message. This means that the Crank Shaft is not in sync with the Intake Camshaft. It could also be a sign of a chain stretch or a jump in the chain link of the upper chain of timing. However the code will not be displayed on its own without additional information from other sensors (G4 and G40).
It is a little tricky to test as there are several connector pins, and each one has different functions. The best way to do it is to measure the resistance between the ECU and the sensor. When the sensor is functional, it should read about 1000 ohms. If you're experiencing issues with this sensor, look for evidence of coolant or oil 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 aren't firing at all. I pulled out the spark plugs this morning, 3 were soaked in gasoline, and the fourth was unclean. When I crank the engine with no sparks, i place a tissue on the top of each of the injector holes, the 3 drenched with gazoline pop out, but the 4th stay shut. I tested the ground connection of ECU pins 14,30, and 48/55. I got 0ohm. Therefore, i think the issue is somewhere else.
I also tried to reset the PID but with no luck. The car click here will start when the G28 is unplugged, and it runs fine with the G28 connected. However, the intermittent misfire problem continues to occur at higher RPM. The coolant sensor (G62), even when it is unplugged, shows temperatures of -49c. Also, i noticed that the oil pressure gauge in the cockpit shows 2 bar while the actual pressure is 0.0 when I crank up the engine.
I'm not sure what to do. I think I've eliminated everything else. I'm concerned that i may 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 check here by the RPM sensor. The GM-style sender is identical to the G4 and both function in the 80 100 200, UrS and RS2 cars so you can easily find one at a wrecking yard or in a local parts store. It is easy to test them: simply switch your DMM into resistance audi key replacement mode and measure the distance between pins 1 and 2 (with the bump at the connector's end facing upwards). They should be infinite Ohms.
4. ECU
Our 20vt turbo (3B, AAN, ABY and ADU) engines have an ECU that has to know the position and speed of the crankshaft in order to make decisions about timing of the fuel injectors, etc. To accomplish this, it makes use of a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If you encounter a problem with either one of these, the diagnostic scanner will show codes that could cause an engine shutdown.
A failing G28 sensor could cause an inaccurate speed counter for your gearbox or a gearbox that shifts faster than normal, or a misfire while in gear. If you are experiencing any of these problems, it is most likely that your sensor is deteriorating and requires replacement. They are cheap and easy-to-find, especially when they're an Bosch model like ours. Alternately, the GM version of this unit is also a great option.
5. Tachometer
A failing engine sensor could cause a number of problems in your car. It's a vital component of your Audi's transmission, as it sends information to the ECU about how the car's crankshaft is rotating. If the sensor fails, it will cause problems for the transmission, as well as the other car's components.
The G5 engine speed sensor is situated on the edge of the transmission just above the flywheel ring gear and sends a signal directly to the ECU at pin T55/49 via an uncolored wire. The ECU is then able to audi keys replacement process this signal to control the flow of fuel, timig and boost, and also sends more info it on to the G5 tachometer in the instrument cluster. You can check the sensor for failure by checking continuity between it and the tachometer, between ECU pin T55/49 and the instrument cluster connection on pin T6a/1 (trace [79trace [79]) and between T6a/1 and the instrument cluster pin T26a/12. You should observe approximately 1000 ohms of resistance between those two pins. This is a common component across the Audi 80 100 200, UrS and RS2 range from 1985 MC through the 1997 UrS AAN and 1995 RS2 ADU so good parts could be found in wrecking yards.