How to Replace an audi car key cover G28 Engine Speed Sensor

In this video Charles the Humble Mechanic shows how to replace the G28 engine speed sensor. The sensor is located on the edge of the transmission above the flywheel ring gear. It transmits a signal to the ECU via a grey wire T55/49, then to the tachometer in the instrument cluster.

1. Engine Speed Sensor

It is located on the outside of the transmission, above the flywheel ring gear G28 Engine Speed Sensor sends a signal to ECU pin T55/49 through the grey wire. The ECU uses this information to control boost and fuel. It also sends an alert to the G5 Tachometer within the instrument cluster.

The sensor is used to link the G40 Camshaft position Sensor. The ecu must be aware when the crankshaft is TDC and where the camshaft is located so that it can start spark and injectors according to the situation.

If this sensor fails when it fails, the ECU will display a P00160 error code. This means that the Crank Shaft is not in sync with the Intake Camshaft. It could also indicate an issue with the chain or a jump in the chain link of the upper chain of timing. However, the error 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 connector pins, and they have different functions but the most effective way to test it is to measure the resistance between the sensor and the ECU. It should read approximately 1000 ohms when it is at full operation. Examine for evidence of coolant or oil in the connector bay if you are experiencing issues with this part.

2. Injectors

Yesterday, when accelerating from highway paytoll at full speed I noticed a massive reduction in power. It was as if the engine was running out of gas. Or, my injectors were not firing. This morning i pull out the spark plugs. Three were drenched with gazoline the 4th one was dry. I placed a tissue over each hole in the injector and when I turn the engine on without sparks, the three with gazoline jump right out. The fourth one remains closed. I checked the ground connection on ECU pins 14/55/30/55/48/55/14/55/48/ I got zero ohm. I think the issue is somewhere else.

I also tried to reset the PID without success. The car will start when the G28 is disconnected, but it runs fine with the G28 connected. However, the intermittent misfire problem still occurs at higher RPM. The temperature sensor for coolant (G62) shows the wrong temperature value of -49c even when i unplug it. I also noticed that the oil gauge in the cockpit shows 2 bar while the actual pressure is zero.

I'm not sure what to do, but i think i've pretty much eliminated everything else. I'm worried that i might have missed something. If anyone has any suggestions, please share them! TIA!

3. Fuel Pump

The fuel pump in the g28 is activated by 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 parts store. It is simple to test them by putting your DMM in resistance mode and take measurements between pins 1 (with the bump on the connector end up) and 2 (2nd from left on the black connector's side). They should be infinite Ohms.

4. ECU

Our 20vt turbo (3B AAN, ABY, and ADU) engines have an ECU that must know the position and speed of the crankshaft in order to make decisions regarding timing of the fuel injectors, etc. To do this, it uses a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If you encounter a problem with either of these, the diagnostic scanner will display codes that could lead to an engine shutdown.

A malfunctioning G28 sensor could cause an inaccurate speed counter replacement key for audi the gearbox and a gearbox which shifts faster than normal, or a misfire while in the gear. If you have any of these problems, it is likely that your sensor is deteriorating and needs replacing. The good thing is that they are very affordable and easily accessible, especially in the case of a Bosch unit which is what we have. If you prefer, GM's version of this part is an excellent choice.

5. Tachometer

A damaged engine sensor could cause a variety of issues within your vehicle. It's an essential component of your Audi Key Shell's transmission, as it sends information to the ECU about how fast or slow the car's crankshaft is spinning. This sensor can cause the transmission to malfunction and other components in the car to be affected.

The G5 engine speed sensor is situated on the edge of the transmission, Audi Car Keys Replacement above the flywheel ring gear and transmits a signal to the ECU at pin T55/49 through a grey wire. The ECU then processes the signal to control fuel, timig, and boost as well as transmitting it to the G5 tachometer inside the instrument cluster. You can test for sensor failure by examining the continuity of the sensor to the tachometer. Also, you can examine the continuity between pins 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. It should show approximately 1000 ohms resistance between these two points. This part is common across the audi key programmer 80-100-200-RS2 series, starting from the 1985 MC all the way up to the 1997 UrS An and 1995 RS2 Du, so you might find good ones in wrecking yards.