Your Worst Nightmare About Audi G28 Bring To Life
How to Replace an audi a3 key replacement G28 Engine Speed Sensor
In this video Charles the Humble Mechanic shows how to replace the G28 engine speed sensor. The sensor is situated near the edges of the transmission, above the flywheel ring gear. It transmits a signal to the ECU via a grey wire T55/49, then to the tachometer located on the instrument cluster.
1. Engine Speed Sensor
Located on the edge of the transmission, above the flywheel ring gear, the G28 Engine Speed Sensor sends a signal to ECU pin T55/49 through the grey wire. The ECU then uses this information to control the boost, fuel, and timig. It also sends an alert to the G5 Tachometer located in the instrument cluster.
The sensor is used as a reference to correlate with the G40 Camshaft Position Sensor. The ecu has to know when the crankshaft reached TDC, and the location of the camshaft so that it can activate the spark and injectors.
If this sensor fails, the ECU will show an error code P00160 which indicates that the Crank Shaft and Intake Camshaft aren't in sync and possibly indicating the chain is stretched or a jump link on the upper timing chain. However, the code won't appear on its own, without additional information from other sensors (G4 and G40).
It's a bit tricky to test since there are several 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. When the sensor is operational, it should be reading around 1000 ohms. Examine for evidence of coolant or audi spare key replacement oil in the connector bay if there are problems with this part.
2. Injectors
Yesterday, when accelerating from highway paytoll at maximum speed I noticed a massive reduction in power. It was as if the engine was running out of gas. Or my injectors weren't firing. In the morning, i removed the spark plugs, 3 were drenched with gazoline the fourth one was dry. I put a piece of tissue over each hole in the injector and when I start the engine without sparks, the three with gazoline jump right out. The 4th one remains closed. I checked the ground connection of ECU pins 14,30 and 48/55. I got 0ohm. I'm assuming that the issue is elsewhere.
I also tried to reset the PID with no success. The car will start when the G28 is disconnected, but it runs fine with the G28 plugged in. However, the intermittent misfire problem continues to occur at higher RPM. The temperature sensor for coolant (G62) shows the wrong temperature value of -49c, even if I unplug it. Also i noticed that the oil pressure gauge in the cockpit is showing 2 bar when the actual pressure is 0.0 when I crank up the engine.
I don't know what to do. I believe that I've eliminated everything else. 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 on the g28 is activated by a signal by the RPM sensor. The GM-style sender 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 junkyard or in a local parts store. It is simple to test them - just switch your DMM into resistance mode and determine the distance between pins 1 and 2 (with the bump at the connector end facing up). They must be infinite Ohms.
4. ECU
Our 20vt turbo (3B, AAN, ABY and ADU) engines are equipped with an ECU that needs to be aware of the speed and position of the crankshaft to make decisions regarding timing of the fuel injectors, etc. To accomplish this, it makes use of a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If either of these goes badly, you will see codes on the diagnostic scanner that could cause engine shut down.
Some of the symptoms of a failing G28 sensor are an inaccurate rev counter for the gearbox, gears shifting quicker than normal and/or a misfire when you are in gear. If you are experiencing any of these issues it is likely your sensor is going bad and needs replacing. They are cheap and easy-to-find especially in the case of a Bosch unit like ours. Alternately, the GM version of this component is also a great option.
5. Tachometer
A malfunctioning engine speed sensor could be a cause replacement key for audi a4 numerous issues in your vehicle. It is an important part of the transmission in your audi keys replacement cost because it relays information to the ECU on how fast or slowly the 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 on the outside of the transmission just above the flywheel ring gear. It sends a signal to the ECU at pin T55/49, via a grey wire. The ECU uses this signal to control the amount of fuel and boost, as well as timig. It also sends it to the G5 Tachometer inside the instrument cluster. You can determine if the sensor is in failure by checking 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. You should detect the resistance to be around 1000 ohms between these points. This is the same across the Audi Tt Key Replacement 80-100-200-RS2 series, starting beginning with the 1985 MC and up to the 1997 UrS AN and Workshop 1995 RS2 DU You may also find good ones in wrecking yards.
