25 Shocking Facts About Audi G28
25 Shocking Facts About 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 near the transmission's edge just above the flywheel gear. It sends a message to the ECU through the grey wire T55/49 and then to the tachometer located on the instrument cluster.
1. Engine Speed Sensor
The grey wire is situated on the edge of transmission, directly above the flywheel ring. The sensor sends signals through the grey wire to pin T55/49. The ECU uses this information to regulate fuel and boost. It also sends an indicator to the G5 Tachometer located in the instrument cluster.
The sensor is used to link the G40 Camshaft position Sensor. The ecu must know when the crankshaft has reached TDC and also the location of the camshaft to trigger the spark and injectors.
If this sensor fails, the ECU will show the P00160 error, which means the Crank Shaft and Intake Camshaft are out of sync and could indicate the chain stretching or a jump link on the upper chain of timing. The code won't appear without the additional information provided by other sensors (G4 or G40).
Testing is a bit challenging as there are two different connector pins, and they have different functions but the most effective way to test it is by measuring resistance between the sensor and the ECU. It should read around 1000 ohms when it is in full operation. If you're experiencing issues with this component, look for signs of oil or coolant in the connector bay.
2. Injectors
Yesterday, while accelerating at full speed from the highway paytoll i had a big cut in power like the engine is out of gas or the injectors aren't firing any more. In the morning, i removed the spark plugs, three were drenched with gazoline the fourth one was dry. When i crank the engine without sparks, i place a tissue on top of each injector hole and the 3 drenched with gazoline pop out, but the 4th stays closed. I tried to test the ground connections of ECU pins 14,30 and 48/55. I found 0ohm. I'm assuming the issue is elsewhere.
I also tried to reset the PID but without success. The car will start when the G28 is disconnected and runs here fine when it is plugged in, but still has the intermittent misfire issue at higher RPM. The coolant sensor (G62) even if it is not plugged in, shows temperatures of -49c. I also noticed that the oil pressure gauge in the cockpit shows 2 bar when the actual pressure is 0.0 read more when I crank up the engine.
I'm not sure what to do, as i believe that i've completely ruled out all other possibilities. But i'm worried that I may have missed something. If anyone has suggestions, please let me know! TIA!
3. Fuel Pump
The fuel pump in the g28 can be activated by a signal sent by the RPM sensor. The GM-style transmitter is identical to the G4 sender, and both website operate on the 80,100,200, UrS, and RS2 vehicles. You can easily find the spare in a salvage shop or parts store. Test them out - put your DMM in resistance mode and take measurements between pins 1 (with the bump on the connector's side up) and 2 (2nd from left on the black end of the connector). 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 in order to make decisions regarding timing of the fuel injector, for example. To accomplish this, it makes use of a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If either of these goes wrong, you will receive codes on the diagnostic scanner which can lead to engine shutdown.
A failing G28 sensor could cause an inaccurate speed counter for the gearbox, a gearbox that shifts faster than normal, or an unfire when in the gear. It is probable that the sensor is failing and needs to be replaced if you encounter any of these symptoms. They're inexpensive and easy to locate especially when they're an Bosch unit like ours. If you prefer, GM's version of this part is a good option.
5. Tachometer
A faulty engine speed sensor could be the reason behind a slew of problems in your car. It's an essential component of your Audi's transmission, because it communicates to the ECU about how fast or slow the car's crankshaft is spinning. This sensor can cause the transmission website to fail and other car components to be affected.
The G5 engine sensor is located near the edge of the transmission, just above the flywheel ring. It sends a signal via gray wire to ECU pin T55/49. The ECU utilizes this signal to control fuel and boost, as well as 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 ECU pin T55/49 and the instrument cluster connection to pin T6a/1 (trace [79trace [79]) as well as between T6a/1, and the instrument cluster pin T26a/12. There should be an average resistance of 1000 ohms in these areas. This is the same across the Audi 80-100-200-RS2 range, from the 1985 MC all the way up to the here 1997 UrS AN and 1995 RS2 DU You may also find some good ones in wrecking yards.