The 3 Greatest Moments In Audi G28 History

How to Replace an audi a3 key replacement G28 Engine Speed Sensor

Charles the Humble Technician shows how to replace the G28 Engine Speed Sensor. This sensor is located at the top of the transmission just above the flywheel ring gear. It sends a signal to the ECU via a grey wire (T55/49), then to the tachometer within the instrument cluster.

1. Engine Speed Sensor

The grey wire is located at the edges of the transmission, just above the flywheel ring. This sensor sends signals through the grey wire to pin T55/49. The ECU then utilizes this information to regulate fuel, timig and boost. It also sends an indication to the G5 tachometer inside the instrument cluster.

The sensor serves as a reference point to connect with the G40 Camshaft Position Sensor. The ecu needs to know when the crankshaft is TDC and the location of the camshaft so it can trigger spark and injectors accordingly.

If this sensor fails the ECU will throw a P00160 code which means the Crank Shaft and Intake Camshaft are out of sync and could indicate 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).

Testing is a bit tricky since there are two connector pins, and they perform different functions however the best method of testing it is by measuring resistance between the sensor and the ECU. It should read about 1000 ohms when it is in full operation. If you're experiencing issues with this part, check for evidence of oil or coolant in the connector bay.

2. Injectors

Yesterday, as i was accelerating off the highway paytoll at a high speed I noticed a massive decrease in power. It was as if the engine had run out of gas. Or my injectors were not firing. I took out the spark plugs this morning and found that 3 were drenched in gasoline and the fourth was unclean. I put a piece of tissue over each injector hole, and when I start the engine without sparks, the 3 with gazoline jump right out. The 4th one stays shut. I tried to test the ground connections of ECU pins 14,30 and 48/55. I found zero ohm. So i assume the problem is somewhere else.

I also tried to reset the PID but with no luck. The car will start when the G28 is disconnected, but it is running fine with the G28 plugged in. However the intermittent misfire issue continues to occur at higher RPM. The coolant sensor (G62), even if it is not plugged in, shows temperatures of -49c. I also noticed that the oil gauge in the cockpit shows 2 bar when the actual pressure is zero.

I'm not sure what to do, but i think i've pretty much completely ruled out all other possibilities. I'm concerned that i may have missed something. Let me know should you have any suggestions! TIA!

3. Fuel Pump

The fuel pump in the g28 receives a signal from the RPM sensor. The GM-style transmitter is similar to the G4 sender, and both operate on the 80,100,200, UrS, and RS2 vehicles. You can easily find an extra in a wrecking shop or a parts store. It is easy to test them - simply put your DMM into resistance mode and test 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 in order to make a decision about timing of the fuel injector, for example. It makes use of a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If you are experiencing issues with either of these, the diagnostic scanner will show codes that could cause an engine shutdown.

Some of the signs of a failed G28 sensor include an inaccurate rev counter in the gearbox, gears shifting quicker than normal and/or a misfire when you're in gear. If you are experiencing any of these issues, it is likely your sensor is deteriorating and requires replacement. The good news is they are very cheap and readily available, especially if you're looking at the Bosch unit which is what ours are. Alternately, GM's version this part would be an excellent choice.

5. Tachometer

A malfunctioning engine speed sensor could be the reason behind numerous problems in your car. It is a crucial part of the audi remote key car key holder (https://www.metooo.es/)'s transmission as it sends information to the ECU about how the car's crankshaft is turning. This sensor could cause the transmission to malfunction and other components of the car to be affected.

The G5 engine sensor is located at the outskirts of transmission, above the flywheel ring. It transmits a signal via gray wire to ECU pin T55/49. The ECU utilizes this signal to regulate the amount of fuel and boost, and also timig. It also transmits 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 observe approximately 1000 ohms resistance between those two pins. This is a standard part that is found across the audi connect key 80 100 200, UrS and RS2 range from 1985 MC until the 1997 UrS AAN and 1995 RS2 ADU. Good ones could be available in wrecking yards.