How to Replace an Audi G28 Engine Speed Sensor
Charles the Humble Technician shows you how to replace the G28 Engine Speed Sensor. The sensor is located on the outside of the transmission just above the flywheel gear. It sends a signal to the ECU via a grey wire (T55/49) and then to the tachometer in the instrument cluster.
1. Engine Speed Sensor
The grey wire is located at the edges of the transmission, above the flywheel ring. The sensor transmits an electrical signal through the grey wire to pin T55/49. The ECU then utilizes this information to regulate the boost, fuel, and timig. It also sends an indication to the G5 Tachometer located in the instrument cluster.
The sensor is used to correlate with the G40 Camshaft position Sensor. The ecu needs to know when the crankshaft is TDC and where the camshaft is so it can activate spark and injectors in the right way.
If this sensor fails, the ECU will throw an error code P00160 which indicates that the Crank Shaft and Intake Camshaft are out of sync and could indicate the chain is stretched or a jump link on the upper timing chain. However, the code won't appear on its own, without additional information from other sensors (G4 and G40).
Testing is a bit challenging as there are two different connector pins, and they have different functions however the best way to test it is by measuring resistance between the sensor and the ECU. When the sensor is operational, it should be reading approximately 1000 ohms. If you're having issues with this component, look for signs of coolant or oil in the connector bay.
2. Injectors
Yesterday, while accelerating at full speed from the highway paytoll i had massive power loss as if the engine was running out of gas or the injectors are not firing anymore. I took out the spark plugs this morning and found that 3 were drenched in gasoline and the fourth 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. I assume that the problem is elsewhere.
I also tried to reset the PID without success. The replacement car key audi key cover audi key replacement near me (click the next internet site) will start when the G28 is disconnected, but it works fine when the G28 connected. However the intermittent misfire issue 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 gauge for oil pressure in the cockpit shows 2 bar, whereas the actual pressure is 0.0 when i rev the engine.
(Image: https://www.g28carkeys.co.uk/wp-content/uploads/2023/11/g28-car-keys-logo-white-green.png)I'm not certain what to do, as i feel i have pretty much eliminated everything else. I'm afraid i may have missed something. If anyone has suggestions, please chime in! TIA!
3. Fuel Pump
The fuel pump in the g28 can be activated by a signal sent by the RPM sensor. The GM-style sender is the same as the G4 and they both work in the 80, 100, 200, UrS and RS2 cars which is why you can easily locate one at a wrecking yard or at a parts store. Testing them is easy - put your DMM in resistance mode and measure the resistance between pins 1 (with the bump on the connector's side up) and 2 (2nd from the left on the black end of the connector). They must be infinite Ohms.
4. ECU
(Image: https://g28carkeys.co.uk/wp-content/uploads/2023/10/Saab-logo.jpg)Our 20vt turbo (3B, AAN, ABY and ADU) engines are equipped with an ECU that must know the speed and position of the crankshaft to make a decision about timing of the fuel injector, for example. It utilizes a Crank Position Sensor G4 and an Engine Speed Sensor G28 to achieve this. If you are experiencing issues with either one of these, the diagnostic scanner will display codes that could cause an engine shut down.
A damaged G28 sensor could result in an inaccurate speed counter for the gearbox and a gearbox which shifts faster than normal, or an unfire when in the gear. It is probable that your sensor is failing and needs to be replaced if you experience any of these symptoms. The good news is they are quite affordable and easy to find particularly if you're looking at the Bosch sensor, which is what ours are. Alternately, GM's version this part is an excellent choice.
5. Tachometer
A failing engine speed sensor could be a cause for a slew of issues in your car. It's an essential component of the transmission in your Audi, as it transmits information to the ECU about how fast or slow the engine is turning. This sensor can cause the transmission to malfunction and other components in the replacement car key audi to be affected.
The G5 engine speed sensor is situated on the edge of the transmission, above the flywheel ring gear and sends a signal directly to the ECU at pin T55/49 through an uncolored wire. The ECU is then able to process the signal to control the flow of fuel, timig and boost, and also sends it on to the G5 tachometer inside the instrument cluster. You can check for sensor failure by examining the continuity from the sensor to the tachometer. Additionally, you can 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 and pin T26a/12. It should show around 1000 ohms of resistance between those two pins. This part is common across the audi connect key 80-100-200-RS2 range, from the 1985 MC all the way up to the 1997 UrS AN and the 1995 RS2 DU So, you may find them in wrecking yards.