25 Unexpected Facts About Audi G28 > 자유게시판

How to Replace an audi Smart key replacement G28 Engine Speed Sensor

In this video Charles the humble mechanic demonstrates how to replace the G28 engine speed sensor. The sensor is located at the top of the transmission just above the flywheel ring gear. It transmits a signal the ECU via an uncolored wire (T55/49), then to the tachometer in the instrument cluster.

1. Engine Speed Sensor

The grey wire is located on the edge of transmission, above the flywheel ring. This sensor sends signals through the grey wire to pin T55/49. The ECU utilizes this information to control the amount of fuel and boost. It also sends an alert to the G5 Tachometer in instrument cluster.

The sensor is used as a reference to correlate 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 start spark and injectors accordingly.

If this sensor fails, the ECU will throw an error code P00160 which indicates that the Crank Shaft and replacement audi key cost Intake Camshaft aren't in sync and could indicate the chain is stretched or a jump link on the upper timing 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 as there are several pins on the connector and each has its own functions. The most effective method to test it is to measure the resistance between the ECU and the sensor. If the sensor is functional, it should read approximately 1000 ohms. If you're having issues with this component, look for signs of oil or coolant in the connector bay.

2. Injectors

Yesterday, while accelerating from the highway paytoll at full speed I noticed a massive reduction in power. It was like the engine had run out of gas. Or my injectors weren't firing. This morning i pull out the spark plugs. Three were soaked with gazoline and the 4th one was dry. When I crank the engine with no sparks, I put a piece of tissue on the top of each of the injector holes and the 3 drenched with gazoline jump out but the 4th stays shut. I tested the ground connection on ECU pins 14/55,30/55 and 48/55 I get 0ohm. I assume that the problem is elsewhere.

I also tried to reset the PID but without success. The car will start when the G28 is unplugged, and it is running fine with the G28 plugged in. However the intermittent misfire issue persists at higher RPM. The temperature sensor for the coolant (G62) shows the wrong temperature of -49c, even if I unplug it. Also i noticed that the gauge for oil pressure in the cockpit shows 2 bar when the actual pressure is 0.0 if i crank up the engine.

I'm not certain what to do, i believe that i've completely ruled out all other possibilities. I'm afraid i may have missed something. Please let me know If you have any suggestions! TIA!

3. Fuel Pump

The fuel pump in the g28 is activated by a signal by the RPM sensor. The GM-style transmitter is identical to the G4 sender, and both operate on the 80,100,200, UrS, and RS2 vehicles. You can easily locate an extra in a wrecking shop or parts store. It is simple to test them by putting your DMM in resistance mode and measure between pins 1 (with the bump on the connector end up) and 2 (2nd from the 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 to make decisions regarding fuel injector timing etc. In order to do this it makes use of a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If you are experiencing issues with either of these, the diagnostic scanner will display the codes that could trigger an engine shut down.

A damaged G28 sensor could result in an inaccurate speed counter for your gearbox or a gearbox that shifts faster than normal, and/or a misfire while in gear. It is likely that the sensor is failing and requires to be replaced if you encounter any of these symptoms. They are cheap and easy-to-find particularly when they're a Bosch model like ours. You can also choose the GM version of this component is also a good choice.

5. Tachometer

A malfunctioning engine sensor can cause a number of problems in your car. It's an essential component of the transmission in your audi a4 replacement key because it relays information to the ECU regarding how fast or slowly the car's engine is turning. This sensor could cause the transmission to fail and other car components to be affected.

The G5 engine speed sensor is located at the outside of the transmission, above the flywheel ring gear and transmits 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 sends it on to the G5 tachometer inside the instrument cluster. You can test the sensor for failure by examining the continuity between it and the tachometer, between the ECU pin T55/49 and the instrument cluster connection via 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 between these two points. This is a standard component across the audi key blade 80, 100, 200, UrS and RS2 range from 1985 MC through the 1997 UrS AAN and 1995 RS2 ADU. Good ones might be availble in wrecking yards.