How to Replace an audi tt key fob Not working G28 Engine Speed Sensor

In this video Charles the Humble Mechanic shows how to replace the G28 engine speed sensor. This sensor is situated at the edge of transmission, http://withsafety.net above the flywheel gear. It sends a signal to the ECU via an uncolored wire (T55/49) and then to the tachometer within 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 using the grey wire. The ECU utilizes this information to control boost and fuel. It also sends signals to the G5 tachometer in 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 where the camshaft is located so that it can trigger spark and injectors according to the situation.

If this sensor fails to function, the ECU will display a P00160 error code. This indicates that the Crank Shaft is not in line with the Intake Camshaft. It could also be a sign of an issue with the chain or a jump in the chain link of the upper chain. However the code will not appear on its own without additional information from other sensors (G4 and G40).

Testing is a bit challenging because there are two connector pins and they serve different purposes but the best way to test it is by measuring resistance between the sensor and the ECU. It should read around 1000 ohms when the sensor is in full operation. Check for signs of coolant, or oil in the connector bay if there are problems with this part.

2. Injectors

Yesterday, as i was accelerating off the highway paytoll at full speed, i noticed a huge decrease in power. It was as if the engine was running out of gas. Or, my injectors were not firing. In the morning, i removed the spark plugs, three were drenched with gazoline the 4th one was dry. I put tissue over each hole in the injector and when I start the engine with no sparks, the three that have gazoline pop right out. The 4th one stays shut. I checked the ground connection on ECU pins 14/55/30/55/48/55/14/55/48/ I get 0ohm. I'm assuming that the issue is elsewhere.

I also tried to reset PID without success. The car will start when the G28 is disconnected, but it is running fine with the G28 plugged in. However the intermittent misfire issue still occurs at higher RPM. The coolant sensor (G62) even when unplugged, still 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 don't know what to do. I feel like i've pretty much eliminated everything else. However, i'm afraid that I might have missed something. Please let me know should you have any suggestions! TIA!

3. Fuel Pump

The fuel pump of the g28 receives signals from the RPM sensor. The GM-style ocated at the outskirts of transmission, above the flywheel ring. It sends a signal via an uncolored wire to the ECU pin T55/49. The ECU then uses and processes this signal to regulate fuel, timig and boost as well as sends it on 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 as well as pin T26a/12. It should show approximately 1000 ohms resistance between those two pins. This is a common component across the audi a1 key 80, 100 200, UrS and RS2 range from 1985 MC until the 1997 UrS AAN and 1995 RS2 ADU so good ones might be availble in wrecking yards.