How To Beat Your Boss On Audi G28
How To Beat Your Boss On Audi G28
Blog Article
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 situated at the edge of transmission over the flywheel gear. It transmits a signal to the ECU via a grey wire T55/49, then to the tachometer on the instrument cluster.
1. Engine Speed Sensor
Located on the edge of the transmission above the flywheel ring gear G28 Engine Speed Sensor sends signals to ECU pin T55/49 through an uncolored wire. The ECU uses this information to control fuel and boost. It also sends an alert to the G5 Tachometer in instrument cluster.
The sensor is used to correlate with the G40 Camshaft position Sensor. The ecu needs to know when the crankshaft has reached TDC and also the location of the camshaft so that it can activate the spark and injectors.
If this sensor fails when it fails, the ECU will display an error code P00160. This means that the Crank Shaft is not in sync with the Intake Camshaft. It could also indicate an issue with the chain or a jumped chain link in the upper chain. The code won't appear without the additional information supplied by other sensors (G4 or G40).
It can be a bit difficult to test since there are different pins on the connector and they all have different functions. The most effective method to test it is to measure the resistance between the ECU and the sensor. It should read approximately 1000 ohms when it is in full operation. Look for signs of coolant, or oil in the connector bay if you have problems with this part.
2. Injectors
Yesterday, while accelerating from the highway paytoll at full speed I noticed a significant reduction 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, 3 were soaked in gasoline, and the fourth was dry. When I crank the engine, there are no sparks, i place a tissue on the top of each hole in the injector and the 3 that were drenched in gazoline pop out, but the 4th one stays shut. I tested the ground connection of ECU pins 14,30 and 48/55. I found zero ohm. I'm assuming the issue is in another place.
I also tried to here reset PID but without success. The car can start if the G28 is unplugged and is running fine when it is connected however it has intermittent misfire issues at higher RPM. The coolant sensor (G62), even when unplugged, still shows an ice temperature of -49c. I also noticed that the gauge for oil check here pressure in the cockpit shows 2 bar, whereas the actual pressure is 0.0 if i crank up the engine.
I don't know what to do. I believe that I've eliminated everything else. I'm afraid i may have missed something. If anyone has suggestions, please share them! TIA!
3. Fuel Pump
The fuel pump in the g28 is activated by a signal from the RPM sensor. The GM-style transmitter is identical to the more info G4 sender and works on the 80,100,200, UrS, and RS2 vehicles. You can easily locate an extra in a wrecking shop or a parts store. Testing them is easy by putting your DMM in resistance mode and measure between pins 1 (with the bump on the connector's end up) and 2 (2nd from left on the black end of the connector). They should be infinite Ohms.
4. ECU
The ECU in our 20vt turbo (3B AAN ABY ADU) engines must know the position and speed the crankshaft in order to make a decision about timing of the fuel injector, etc. To accomplish this, it uses a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If either of these sensors go wrong, you will receive codes on the diagnostic scanner which can lead to engine shutdown.
A failing G28 sensor could result in an inaccurate gearbox speed counter, a gearbox that shifts faster than normal, and/or a misfire while in the gear. It is likely that the sensor is failing and needs to be replaced if you experience any of these signs. They are cheap and easy-to-find, especially if they're an Bosch model like ours. Alternately, GM's version this part would be a good option.
5. Tachometer
A damaged engine sensor could cause a number of problems in your car. It's a crucial component of the transmission in your Audi because it relays information to the ECU about how fast or slow the car's engine is spinning. This sensor can cause the transmission to fail and other car components to be affected.
The G5 engine speed sensor is situated on the edge of the transmission above the flywheel ring gear. It sends a signal to the ECU at pin T55/49 via an uncolored wire. The ECU then uses and processes the signal to control fuel, timig and boost and then transmitting it to here 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 via pin T6a/1 (trace [79]) and between pin T6a/1 and the instrument cluster pin T26a/12. It should show approximately 1000 ohms resistance between those two pins. This is a standard part across the Audi 80, 100 200, get more info UrS and RS2 range from 1985 MC to the 1997 UrS AAN and 1995 RS2 ADU so good parts could be found in wrecking yards.