How to Replace an Audi G28 Engine Speed Sensor
Charles the Humble Technician teaches you how to replace the G28 Engine Speed Sensor. This sensor is located on the outside of the transmission over the flywheel gear. It transmits a signal to the ECU through a grey wire T55/49, then to the tachometer located on the instrument cluster.
1. Engine Speed Sensor
It is located on the outside of the transmission, above the flywheel ring gear the G28 Engine Speed Sensor sends a signal to ECU pin T55/49 using the grey wire. The ECU then utilizes this information to regulate the boost, fuel, and timig. It also sends a signal to the G5 tachometer inside the instrument cluster.
The sensor is used to connect with the G40 Camshaft position Sensor. The ecu has to know when the crankshaft has reached TDC and also the position of the camshaft, to trigger the spark and injectors.
If this sensor fails, the ECU will show a P00160 code which means the Crank Shaft and Intake Camshaft are not in sync and could indicate chain stretch or a jumped link on the upper timing chain. However, the code won't appear on its own, without additional information from other sensors (G4 and G40).
Testing can be a bit difficult because there are two pins for the connector and they have different functions but the most effective method to test it is to measure the resistance between the sensor and the ECU. If the sensor is operational, it should read about 1000 ohms. If you're having issues with this sensor, look for evidence of coolant or oil in the connector bay.
2. Injectors
Yesterday, when i was accelerating to the fullest speed from highway paytoll, I experienced a big cut in power like the engine is running out of gas or injectors are not firing any more. In the morning, i removed the spark plugs. Three were drenched with gazoline the 4th one was dry. I put a piece of tissue over each injector hole, and when I turn the engine on without sparks, the 3 with gazoline jump right out. The 4th one stays closed. I tested the ground connection on ECU pins 14/55, 30/55 and 48/55. I get zero ohm. I assume that the problem is somewhere else.
I also tried to reset the PID with no success. The car will start when the G28 is unplugged, and it runs fine with the G28 plugged in. However the intermittent misfire issue continues to occur at higher RPM. The temperature sensor for the coolant (G62) shows the wrong temp value -49c, even if I unplug it. I also noticed that the oil gauge in the cockpit shows 2 bar but the actual pressure is zero.
I'm not sure what to do, i believe that i've completely ruled out all other possibilities. I'm concerned that i may have missed something. Let me know If you have any suggestions! TIA!
3. Fuel Pump
The fuel pump in the g28 can be activated by a signal sent from the RPM sensor. The GM-style transmitter is similar to the G4 sender and both work on the 80,100,200, UrS, and RS2 vehicles. You can here easily locate a spare in a wrecking shop or a parts store. Testing them is easy by putting your DMM in resistance mode and take measurements between pins 1 (with the bump on the connector's end up) and 2 (2nd from the left on the black connector's end). They should be infinite Ohms.
4. ECU
The ECU of our 20vt turbo (3B AAN ABY) engines requires to know both the speed and position of the crankshaft to determine fuel injector timing, etc. To do this, it makes use of 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 that can lead to engine shutdown.
A malfunctioning G28 sensor could cause an inaccurate speed counter for your gearbox, a gearbox that shifts faster than more info normal, and/or a misfire while in gear. It is possible that the sensor is failing advanced key audi and requires to be replaced if you notice any of these signs. They're inexpensive and easy to locate particularly when they're a Bosch unit like ours. Alternately, GM's version this part is an excellent choice.
5. Tachometer
A damaged engine sensor could cause a variety of issues in your car. It's a crucial component of the transmission in your Audi, as it transmits information to the ECU regarding 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 sensor is located at the edge of the transmission, over the flywheel ring. audi a4 key replacement It sends signals via an uncolored wire to the ECU pin T55/49. The ECU uses this signal to regulate the amount of fuel and boost, as well as timig. It also transmits it to the G5 Tachometer in 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]) as well as between T6a/1, and the instrument cluster pin T26a/12. There should be the resistance to be around 1000 ohms between these two points. This is a common feature across the Audi more info 80-100-200-RS2 model, ranging beginning with the 1985 MC and up to the 1997 UrS AN and 1995 RS2 DU You may also find some good ones in wrecking yards.