How to Replace an audi keys replacement G28 Engine Speed Sensor
Charles the Humble Technician teaches you how to replace the G28 Engine Speed Sensor. This sensor is located near the transmission's edge over the flywheel gear. It sends a message to the ECU through a grey wire T55/49, then to the tachometer located on 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 utilizes this information to regulate boost and fuel. It also sends an indication to the G5 tachometer inside 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 where the camshaft is so it can start spark and Audi Key Fob Not Working injectors accordingly.
If this sensor fails the ECU will display a P00160 code 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. The code won't show without the additional information provided by other sensors (G4 or G40).
It is a little tricky to test since there are various pins on the connector and each one has different functions. The best way to do it is to measure the resistance between the ECU and the sensor. It should read around 1000 ohms when the sensor is at full operation. If you're having issues with this part, check for signs of oil or coolant in the connector bay.
2. Injectors
Yesterday, while accelerating at full speed from the highway paytoll, i experienced a big cut in power as if the engine was running out of gas or the injectors aren't firing anymore. I took out the spark plugs this morning and found that 3 were drenched in gasoline and the 4th was dry. When I start the engine without sparks, I put a piece of tissue on the top of each hole in the injector, the 3 drenched with gazoline jump out but the 4th one stays shut. I tried to test the ground connections of ECU pins 14,30 and 48/55. I got zero ohm. So i assume the problem is in another place.
I also tried to reset the PID but with no luck. The car is able to start if the G28 is unplugged and runs fine when it is plugged in but it still has intermittent misfire issues at higher RPM. The coolant sensor (G62), even when it is unplugged, shows an ice temperature of -49c. I also noticed that the oil gauge in the cockpit shows 2 bars when the actual pressure is 0.
I'm not sure what to do, as i feel i have pretty much ruled out everything else. I'm concerned that i may have missed something. If anyone has any ideas please share them! TIA!
3. Fuel Pump
The fuel pump on the g28 is activated by a signal sent 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 the spare audi key in a salvage shop or a parts store. Testing them is easy by putting your DMM in resistance mode and measure the resistance between pins 1 (with the bump on the connector end up) and 2 (2nd from the left on the black connector's side). They should be infinite Ohms.
4. ECU
The ECU in our 20vt turbo (3B AAN ABY) engines must know both the position and speed of the crankshaft to determine timing of the fuel injector, etc. It utilizes a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If you are experiencing issues with either of these, the diagnostic scanner will show codes that could lead to an engine shutdown.
Some of the symptoms of a failing G28 sensor include an inaccurate gearbox rev counter and gears that shift faster than normal and/or a misfire when you're in gear. It is possible that your sensor is failing and needs to be replaced if you experience any of these symptoms. They're inexpensive and easy to locate particularly in the case of an Bosch model like ours. Alternately, the GM version of this part is also a good choice.
5. Tachometer
A malfunctioning engine sensor can cause a variety of issues in your vehicle. It is a crucial part of your audi car key replacement's transmission, since it relays information to the ECU about how the car's crankshaft is spinning. If this sensor fails, it will cause problems for the transmission as well as the other car's components.
The G5 engine speed sensor is located at the edge of the transmission just above the flywheel ring gear. It transmits a signal to the ECU at pin T55/49, via an uncolored wire. The ECU uses this signal to control fuel and boost, as well as timig. It also relays it to the G5 Tachometer inside the instrument cluster. You can check the sensor for any failure by checking the continuity between it and the tachometer, between ECU pin T55/49 and the instrument cluster connection via pin T6a/1 (trace [79]) and audi tt key fob not working between T6a/1 and the instrument cluster pin T26a/12. You should see an average resistance of 1000 ohms in these areas. This is a common feature across the audi Spare key Cost 80-100-200-RS2 range, from the 1985 MC up to the 1997 UrS AN and the 1995 RS2 Du You may also find good ones in wrecking yards.