7 Little Changes That Will Make A Huge Difference In Your Audi G28

How to Replace an Audi G28 Engine Speed Sensor

Charles the Humble Technician shows how to replace the G28 Engine Speed Sensor. This sensor is located on the outside of the transmission just above the flywheel gear. It transmits a signal to the ECU through a grey wire T55/49, then to the tachometer on the instrument cluster.

1. Engine Speed Sensor

The sensor is located at the edge of the transmission just above the flywheel ring gear G28 Engine Speed Sensor sends signals to ECU pin T55/49 via a grey wire. The ECU utilizes this information to regulate boost and fuel. It also sends an alert to the G5 Tachometer in instrument cluster.

The sensor serves as a reference for comparing with the G40 Camshaft Position Sensor. The ecu must be aware when the crankshaft is TDC and the location of the camshaft so it can trigger spark and injectors in the right way.

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. However the code will not 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 however the best method of testing it is to measure resistance between the sensor and the ECU. It should read around 1000 ohms when it is in full operation. Examine for evidence of coolant or oil in the connector bay if you have issues with this part.

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 out of gas or the injectors are not firing anymore. Today, i pulled out the spark plugs, 3 were drenched with gazoline the fourth was dry. I placed a tissue over each injector hole and when I start the engine without sparks, the three with gazoline jump out. The 4th one remains closed. I checked the ground connection on ECU pins 14/55,30/55 and 48/55 I got 0ohm. I assume that the problem is elsewhere.

I also tried to reset the PID with no success. The car will start when the G28 is disconnected, but it works fine when 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 a temperature of -49c. I also noticed get more info that the gauge for oil pressure in the cockpit is showing 2 bar when the actual pressure is 0.0 if i crank up the engine.

I'm not sure what to do. I think I've all other possibilities out. 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 gets a signal from the RPM sensor. The GM-style transmitter is the same as the G4 and both are used in the 80, 100 200, here UrS and RS2 cars so you can easily find one at a junkyard or at a parts store. It is easy to test them: simply switch your DMM into resistance mode and test the distance between pins 1 and 2 (with the bump on the connector's edge facing upwards). They should be infinite ohms.

4. ECU

The ECU of our 20vt turbo (3B AAN ABY) engines needs to know read more both the audi a4 car key replacement position and speed the crankshaft to make decisions regarding timing of the fuel injector, etc. It makes use of a Crank Position Sensor G4 and an Engine Speed Sensor G28 to achieve this. If you encounter a problem with either one of these, the diagnostic scanner will display codes that could lead to an engine shutdown.

A failing G28 sensor could cause an inaccurate speed counter for the gearbox and a gearbox which shifts more quickly than normal, or a misfire while in gear. It is likely that your sensor is failing and needs to be replaced if you notice any of these signs. They're cheap and easy to find especially if they're a Bosch model like ours. Alternately, GM's version this part would be an excellent choice.

5. Tachometer

A malfunctioning engine sensor can cause a myriad of issues in your website car. It's a crucial component of the transmission of your Audi since it sends information to the ECU about how fast or slowly the engine of the car is spinning. When this sensor fails, it can disrupt the performance of the transmission, as well as the rest of the car's components.

The G5 engine sensor is located at the edge of transmission, above the flywheel ring. It transmits an electrical signal through an uncolored wire to the ECU pin T55/49. The ECU then uses and processes the signal to control fuel, timig, and boost, and also transmitting it to the G5 tachometer inside the instrument cluster. You can determine if the sensor is in failure by examining the continuity from the sensor to the tachometer. You can also examine the continuity between pins T55/49 of the ECU and pin T6a/1 of the instrument cluster (trace [79]), and between pin T6a/1 and pin T26a/12. You should observe around 1000 ohms of resistance between those two pins. This is a typical part across the Audi 80 100, 200, UrS and RS2 range from 1985 MC to the 1997 UrS AAN and 1995 RS2 ADU so good ones could be available in wrecking yards.