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 at the edge of transmission, above 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 situated on the outside of the transmission, directly above the flywheel ring. This sensor sends an electrical signal through the grey wire to pin T55/49. The ECU uses this information to regulate boost and fuel. It also sends a signal to the G5 tachometer in the instrument cluster.
The sensor is used to link with the G40 Camshaft position Sensor. The ecu needs to know when the crankshaft is TDC and where the camshaft is located so that it can activate spark and injectors in the right way.
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 be a sign of an issue with the chain or a jump in the chain link of the upper chain of timing. However, the code won't appear on its own, without additional information from other sensors (G4 and G40).
It is a little tricky to test because there are different connector pins, and they all have different functions. The best method for doing this is by measuring the resistance between the ECU and the sensor. It should read approximately 1000 ohms when the sensor is at full operation. If you're experiencing issues with this part, check for signs of coolant or oil in the connector bay.
2. Injectors
Yesterday, while accelerating from the highway paytoll at maximum speed I noticed a significant reduction in power. It was as if the engine was running out of gas. Or, my injectors were not firing. Today, i pulled out the spark plugs, 3 were drenched with gazoline the 4th one was dry. When i crank the engine with no sparks, I put a piece of tissue on top of each injector hole and the 3 drenched with gazoline leap out, however the 4th one stays closed. I checked the ground connection on ECU pins 14/55/30/55/48/55/14/55/48/ i get zero ohm. I think the issue is in another location.
I also tried to reset the PID but without success. The car will start if the G28 is not plugged in and runs fine when it is plugged in however it has intermittent misfire issues at higher RPM. The coolant sensor (G62), even if it is not plugged in, shows an ice 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 if i crank up the engine.
I'm not sure what to do, i think i've pretty much eliminated everything else. However, i'm afraid that i might have missed something. If anyone has any ideas please chime in! TIA!
3. Fuel Pump
The fuel pump in the g28 is activated by a signal sent by the RPM sensor. The GM-style sensor is identical to the G4 and both are used in the 80, 100, 200, UrS and RS2 cars which is why you can easily locate one at a salvage yard or from a parts store. It is simple to test them: simply put your DMM into resistance mode and test the distance between pins 1 and 2 (with the bump at the connector end facing upwards). They should be infinite ohms.
4. ECU
The ECU in our 20vt turbo (3B AAN ABY ADU) engines requires to know the position and speed the crankshaft in more info order to make a decision about timing of fuel injectors, etc. In order to do this it uses a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If either of these check here sensors go wrong, you will receive codes on the diagnostic scanner which can cause the engine to shut down.
The signs of a failed G28 sensor include an inaccurate rev counter for the gearbox the gears are shifting faster than normal, and/or a misfire when in gear. It is possible that your sensor is failing and requires to be replaced if you experience any of these signs. They're inexpensive and easy to locate, especially when they're an Bosch unit like ours. Alternately, GM's version this part is an excellent choice.
5. Tachometer
A malfunctioning engine speed sensor could be the cause of a slew of issues with your car. It is click here a crucial part of your Audi's transmission, because it communicates to the ECU about how the car's crankshaft is turning. This sensor could cause the transmission to malfunction and other components of the car to be affected.
The G5 engine sensor is located at the edge of transmission, above the flywheel ring. It sends signals via a gray wire to the ECU pin T55/49. The ECU is then able to process this more info signal to control fuel, timig and boost and then sends it on to the G5 tachometer in the instrument cluster. You can check for sensor failure by examining the continuity from the sensor to the tachometer. You can also check continuity between pin T55/49 of the ECU and pin T6a/1 of the instrument cluster (trace [79trace [79]) and between pin T6a/1 and pin T26a/12. There should be an average resistance of read more 1000 ohms between these two points. This is a common feature across the Audi 80-100-200-RS2 series, starting beginning with the 1985 MC and up to the 1997 UrS An and 1995 RS2 DU So, you may find some good ones in wrecking yards.