What Is Audi G28 History Of Audi G28

How to Replace an audi key copy G28 Engine Speed Sensor

Charles the Humble Technician shows you how to replace the G28 Engine Speed Sensor. The sensor is situated on the edge of the transmission just above the flywheel ring gear. It transmits a signal to the ECU via the grey wire (T55/49) which is then sent to the tachometer in 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 signals to ECU pin T55/49 through an uncolored wire. The ECU then utilizes this information to regulate the flow of fuel, timig and boost. It also sends an indicator to the G5 Tachometer located in the instrument cluster.

The sensor serves as a reference for comparing 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 show the P00160 error, which means the Crank Shaft and Intake Camshaft aren't in sync and could indicate the chain is stretched 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 is a bit tricky as there are two different pins for the connector and they perform different functions but the most effective method to test it is to measure resistance between the sensor and the ECU. When the sensor is operational, it should read about 1000 ohms. Check for signs of coolant, or oil in the connector bay if you have problems with this part.

2. Injectors

Yesterday, while accelerating from the highway paytoll at a high speed I noticed a significant decrease in power. It was as if the engine had run out of gas. Or my injectors were not firing. I pulled out the spark plugs this morning and found that 3 were drenched in gasoline and the fourth was unclean. When i crank the engine, there are no sparks, i place a tissue on the top of each hole in the injector and the 3 drenched with gazoline jump out but the 4th stay shut. I inspected the ground connection on ECU pins 14/55/30/55/48/55/14/55/48/ I get 0ohm. I think the issue is elsewhere.

I also tried to reset the PID without success. The car is able to start if the G28 is unplugged and it runs perfectly when it is connected however it has intermittent misfire issues at higher RPM. The coolant sensor (G62) even if it is not plugged in, shows an ice temperature 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. I feel like i've pretty much all other possibilities out. However, i'm afraid that i might have missed something. If anyone has any ideas please let me know! TIA!

3. Fuel Pump

The fuel pump in the g28 can be activated by a signal 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. It is easy to find a spare in a wrecking shop or parts store. Testing them is easy by putting your DMM in resistance mode and measure between pins 1 (with the bump on the connector's side up) and 2 (2nd from the left on the black connector's end). They must be infinite Ohms.

4. ECU

Our 20vt turbo (3B, AAN, ABY and ADU) engines are equipped with an ECU that has to be aware of the speed and position of the crankshaft to make a decision about fuel injector timing etc. It uses a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If either of these goes wrong, you will receive codes on the diagnostic scanner which can lead to engine shutdown.

A failing G28 sensor could cause an inaccurate speed counter for the gearbox or a gearbox that shifts faster than normal, and/or a misfire while in gear. If you are experiencing any of these problems, it is likely that your sensor is going bad and needs replacing. They are cheap and easy-to-find, especially when they're a Bosch sensor like ours. Alternately, the GM version of this component is also a good option.

5. Tachometer

A faulty engine speed sensor could be the reason behind many problems in your car. It is an important part of the transmission in your audi key replacement Car key case (metooo.it), as it transmits information to the ECU regarding how fast or slow the engine is spinning. When this sensor fails, it could cause problems for the transmission, as well as the rest of the car's components.

The G5 engine sensor is located at the edge of the transmission, over the flywheel ring. It transmits a signal via gray wire to ECU pin T55/49. The ECU then processes the signal to control fuel, timig, and boost and then transmitting it to the G5 tachometer in the instrument cluster. You can determine if the sensor is in failure by examining the continuity of the sensor to the tachometer. Additionally, you can 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 as well as pin T26a/12. You should see approximately 1000 ohms resistance between those two pins. This is the same across the audi keyless entry 80-100-200-RS2 series, starting beginning with the 1985 MC and up to the 1997 UrS AN and the 1995 RS2 DU So, you may find good ones in wrecking yards.