Why No One Cares About Audi G28
Why No One Cares About Audi G28
Blog Article
How to Replace an Audi G28 Engine Speed Sensor
In this video Charles the Humble Mechanic shows how to replace the G28 engine speed sensor. The sensor is located at the edge of transmission over the flywheel gear. It sends a message to the ECU via a grey wire T55/49, then to the tachometer located on 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 an electrical signal to ECU pin T55/49 using a grey wire. The ECU utilizes this information to regulate the amount of fuel and boost. It also sends a signal to the G5 tachometer inside the instrument cluster.
The sensor is used to connect with the G40 Camshaft position Sensor. The ecu must know when the crankshaft is TDC and the location of the camshaft so it can activate spark and injectors accordingly.
If this sensor fails, the ECU will show the P00160 error, which means the Crank Shaft and Intake Camshaft are out of sync and could indicate chain stretch or a jumped link on the upper chain of timing. 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 perform different functions but the best method to test it is by measuring resistance between the sensor and the ECU. When the sensor is fully operational, it should be reading about 1000 ohms. If you are having problems with this sensor, look for signs of coolant or oil in the connector bay.
2. Injectors
Yesterday, as i was accelerating off the highway paytoll at full speed I noticed a massive reduction in power. It was as if the engine had run out of gas. Or my injectors weren't firing. Today, i pulled out the spark plugs, three were drenched with gazoline the fourth one was dry. I placed a tissue over each hole in the injector and when I start the engine without sparks, the three with gazoline jump out. The 4th one remains shut. I tested the ground connection on ECU pins 14/55, 30/55 and 48/55. I got zero Ohm. So i assume the problem is in another place.
I also tried to reset the PID but without success. The car can start read more when the G28 is disconnected and runs fine when it is connected however it is experiencing intermittent misfires at higher website RPM. The coolant temperature sensor (G62) shows the wrong temperature of -49c, even if I unplug it. I also noticed that the oil gauge in the cockpit shows 2 bars while the actual pressure is 0.
I'm not sure what to do. I believe that I've ruled everything else out. I'm concerned that i may have missed something. Let me know should you have any suggestions! TIA!
3. Fuel Pump
The fuel website pump of the g28 receives signals from the RPM sensor. The GM-style sensor is identical to the G4 and both are used 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. Test them out more info - put your DMM in resistance mode and measure 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 needs to know the speed and position of the crankshaft to make a decision about timing of the fuel injector, for example. It makes use of a Crank Position Sensor G4 and an Engine Speed Sensor G28 to achieve this. If you have a problem with either of these, the diagnostic scanner will display the codes that could trigger an engine shut down.
A malfunctioning G28 sensor could result in an inaccurate speed counter for the gearbox, a gearbox that shifts more quickly than normal, and/or an unfire when in the gear. If you have any of these issues it is likely that your sensor is going bad and needs replacing. They're inexpensive and easy to locate particularly in the case of an Bosch unit like ours. Alternately, the GM version of this unit is also a good choice.
5. Tachometer
A damaged engine sensor could cause a number of problems in your vehicle. It is a crucial part of your Audi's transmission, because it communicates to the ECU about how the car's crankshaft is turning. When this sensor fails, it could affect the performance of the transmission, as well as the rest of the car's components.
The G5 engine sensor is located at the outskirts of transmission, above the flywheel ring. It sends signals via an uncolored wire to the ECU pin T55/49. The ECU then processes this signal to control the flow of fuel, timig and boost, and also transmitting it to the G5 tachometer inside the instrument cluster. You can check for sensor failure by examining the continuity of the sensor to the tachometer. Additionally, you can check continuity between pin T55/49 of the ECU and pin T6a/1 of the instrument cluster (trace [79trace [79]), and between pin T6a/1 and pin T26a/12. You should see read more approximately 1000 ohms resistance between these two points. This is a common part across the Audi 80 100 200, UrS and RS2 range from 1985 MC until the 1997 UrS AAN and 1995 RS2 ADU, so the best parts could be found in wrecking yards.