10 Quick Tips About Audi G28

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

In this video Charles the Humble Mechanic demonstrates how to replace the G28 engine speed sensor. The sensor is located near the transmission's edge just above the flywheel gear. It transmits a signal to the ECU through the grey wire T55/49 and then to the tachometer on the instrument cluster.

1. Engine Speed Sensor

The grey wire is located on the outside of the transmission, directly above the flywheel ring. This sensor sends an electrical signal through the grey wire to pin T55/49. The ECU utilizes this information to control fuel and boost. It also sends an indication to the G5 Tachometer in instrument cluster.

The sensor is used 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 start spark and injectors according to the situation.

If this sensor fails, the ECU will show the P00160 error, which means the Crank Shaft and Intake Camshaft aren't in sync and possibly indicating chain stretch or a jumped link on the upper chain of timing. However, the code won't be displayed on its own without additional information from other sensors (G4 and G40).

Testing is a bit challenging because there are two pins for the connector and they perform different functions however the best way to test it is to measure the resistance between the sensor and the ECU. It should read around 1000 ohms when it is operating at its maximum. Examine for evidence of coolant or oil in the connector bay if you are experiencing problems 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 at all. I took out the spark plugs this morning, 3 were soaked with gasoline and the 4th was dry. I put a piece of tissue over each hole in the injector and when I start the engine with no sparks, the 3 with gazoline jump right out. The fourth one remains shut. I tested the ground connection on ECU pins 14/55,30/55 and 48/55 I get 0ohm. So i assume the problem is elsewhere.

I also tried to reset the PID but without success. The car will start when the G28 is unplugged, and it works fine when the G28 plugged in. However, the intermittent misfire problem persists 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 bars but the actual pressure is zero.

I'm not certain what to do, but i believe that i've completely ruled out all other possibilities. But i am afraid i might have missed something. If anyone has any ideas please chime in! TIA!

3. Fuel Pump

The fuel pump in the g28 receives signals from the RPM sensor. The GM-style transmitter is identical to the G4 sender and both work on the 80,100,200, UrS, and RS2 vehicles. It is easy to find the spare in a salvage shop or replacement audi car key Tt key audi - Youtube.Com - parts store. It is easy to test them - just 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 should be infinite ohms.

4. ECU

Our 20vt turbo (3B AAN, ABY and ADU) engines have an ECU that needs to know the speed and position of the crankshaft in order to make decisions regarding timing of the fuel injectors, etc. To accomplish this, it uses a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If either of these go wrong, you will receive codes on the diagnostic scanner that could cause engine shut down.

A malfunctioning G28 sensor could result in 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 issues it is likely that your sensor is failing and needs replacing. They're cheap and easy to find particularly if they're a Bosch unit like ours. Alternately, the GM version of this component is also a great option.

5. Tachometer

A failing engine speed sensor could be a cause for a slew of problems in your vehicle. It is an important part of the transmission in your Audi car key holder since it sends information to the ECU regarding how fast or slow the engine is turning. When this sensor fails, it can affect the performance of the transmission and the rest of the car's components.

The G5 engine speed sensor is situated on the edge of the transmission just above the flywheel ring gear and sends a signal directly to the ECU at pin T55/49 via an uncolored wire. The ECU is then able to process the signal to control fuel, timig and boost, and also sends it on to the G5 tachometer in the instrument cluster. You can test the sensor for failure by examining the continuity between it and the tachometer, between the ECU pin T55/49 and the instrument cluster connection to pin T6a/1 (trace [79trace [79]) and between pin T6a/1 and the instrument cluster pin T26a/12. You should see an average resistance of 1000 ohms in these areas. This is a typical part across the audi car key case 80 100 200, UrS and RS2 range from 1985 MC to the 1997 UrS AAN and 1995 RS2 ADU. Good parts could be found in wrecking yards.