The No. #1 Question That Everyone In Audi G28 Must Know How To Answer
The No. #1 Question That Everyone In Audi G28 Must Know How To Answer
Blog Article
How to Replace an Audi G28 Engine Speed Sensor
Charles the Humble Technician teaches how to replace the G28 Engine Speed Sensor. The sensor is located near the edges of the transmission, above the flywheel ring gear. It transmits a signal to the ECU via an uncolored wire (T55/49) and then to the tachometer within the instrument cluster.
1. Engine Speed Sensor
The grey wire is situated on the edge of transmission, just above the flywheel ring. The sensor sends a signal via the grey wire to pin T55/49. The ECU utilizes this information to control the amount of fuel and boost. It also sends an indication 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 be aware when the crankshaft is TDC and where the camshaft is so it can activate spark and injectors in the right way.
If this sensor fails, the ECU will display a P00160 error code. This means that the Crank Shaft is out of sync with the Intake Camshaft. It could also indicate a chain stretch or a jumped chain link in the upper timing chain. However the code will not appear on its own without additional information from other sensors (G4 and G40).
Testing is a bit tricky as there are two different connector pins, and they serve different purposes but the most effective method of testing it is to measure resistance between the sensor and the ECU. It should read approximately 1000 ohms when the sensor is in full operation. If you are having problems with this sensor, look for signs of oil or coolant in the connector bay.
2. Injectors
Yesterday, as i was accelerating off the highway paytoll at full speed I noticed a massive drop in power. It was as if the engine had run out of gas. Or, my injectors were not firing. I pulled out the spark plugs this morning and found that 3 were drenched in gasoline and the fourth was unclean. When I crank the engine without sparks, i place a tissue on top of each injector hole and the 3 that were drenched in gazoline jump out but the 4th one stays shut. I tested the ground connection of ECU pins 14,30, and 48/55. I found 0ohm. I'm assuming the issue is in another place.
I also tried to reset PID without success. The car will start if the G28 is unplugged and it runs perfectly when it is connected, but still has intermittent misfire issues at higher RPM. The coolant sensor (G62), even if it is not plugged in, shows more info an ice get more info temperature of -49c. Also, i noticed that the oil pressure gauge in the cockpit is showing 2 bar while the actual pressure is 0.0 if i crank up the engine.
I don't know what to do. I feel like i've pretty much all other possibilities out. However, i'm afraid that i might have missed something. If anyone has any ideas please let me know! TIA!
3. Fuel Pump
The fuel pump in the g28 receives signals from the RPM sensor. The GM-style sensor 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 salvage yard or in a local parts store. It is simple to test them - simply switch your here DMM into resistance mode and test the distance between pins 1 and 2 (with the bump at the connector end facing up). They should be infinite ohms.
4. ECU
Our 20vt turbo (3B, AAN, ABY and ADU) engines have an ECU that needs to know the position and speed of the crankshaft in order to make decisions about fuel injector timing etc. It utilizes a Crank Position Sensor G4 and an Engine Speed more info Sensor G28 to achieve this. If you have a problem with either of these sensors, the diagnostic scanner will show codes that could cause an engine shutdown.
The signs of a failed G28 sensor include an inaccurate rev counter for the gearbox the gears are shifting faster than normal and/or misfiring when you here are in gear. If you experience any of these issues, it is likely your sensor is going bad and requires replacement. They're cheap and easy to find, especially when they're an Bosch unit like ours. If you prefer, GM's version of this component is an excellent choice.
5. Tachometer
A failing engine sensor could cause a variety of issues in your car. It's an essential component of the transmission of your Audi since it sends information to the ECU regarding how fast or slow the car's engine is spinning. This sensor can cause the transmission to malfunction and other components of the car to be affected.
The G5 engine sensor is located at the outskirts of the transmission, just above the flywheel ring. It sends an electrical signal through an uncolored wire to the ECU pin T55/49. The ECU uses this signal to regulate the flow of fuel and boost and also timig. It also transmits it to the G5 Tachometer inside the instrument cluster. You can test the sensor for failure by checking continuity between it and the tachometer, between the ECU pin T55/49 and the instrument cluster connection via pin T6a/1 (trace [79trace [79]) and between pin T6a/1 and the instrument cluster pin T26a/12. You should see a resistance of approximately 1000 ohms in these areas. This is the same across the Audi 80-100-200-RS2 series, starting from the 1985 MC all the way up to the 1997 UrS AN and the 1995 RS2 Du, so you might find them in wrecking yards.