The Top Reasons For Audi G28's Biggest "Myths" About Audi G28 Might Be True
The Top Reasons For Audi G28's Biggest "Myths" About Audi G28 Might Be True
Blog Article
How to Replace an Audi G28 Engine Speed Sensor
Charles the Humble Technician teaches you how to replace the G28 Engine Speed Sensor. This sensor is located near the edges of the transmission, above the flywheel ring gear. It transmits a signal to the ECU via the grey wire (T55/49), then to the tachometer located in the instrument cluster.
1. Engine Speed Sensor
The grey wire is located at the edges of the transmission, directly above the flywheel ring. This sensor sends signals through the grey wire to pin T55/49. The ECU utilizes this information to regulate fuel and boost. 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 must 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 display the P00160 error, which means the Crank Shaft and Intake Camshaft aren't in sync and could indicate chain stretch or a jumped 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 can be a bit difficult because there are two connector pins and they perform different functions however the best way to test it is by measuring resistance between the sensor and the ECU. It should read approximately 1000 ohms if the sensor is in full operation. If you're having issues with this part, check for evidence of coolant or oil in the connector bay.
2. Injectors
Yesterday, when accelerating from highway paytoll at a high speed, i noticed a huge reduction in power. It was like the engine was running out of gas. Or my injectors weren't firing. Today, i pulled out the spark plugs, 3 were drenched in gazoline, the 4th one was dry. When I crank the engine with no sparks, I put a piece of tissue on the top of each of the injector holes and the 3 that were drenched in gazoline pop out, but the 4th stay shut. I checked the ground connection of ECU pins 14,30 and 48/55. I found zero ohm. I'm assuming the issue is somewhere else.
I also tried to reset website PID without success. The car can start when the G28 is not plugged in and it runs perfectly when it is connected but it still is experiencing intermittent misfires at higher RPM. The coolant sensor (G62), even when unplugged, still shows temperatures of -49c. I also noticed that the gauge for oil pressure in the cockpit shows 2 bar while the actual pressure is 0.0 when i rev the engine.
I'm not sure what to do. I believe that I've all other possibilities out. I'm concerned that i may have missed something. If anyone has suggestions, please share them! TIA!
3. Fuel Pump
The fuel pump of the g28 gets a signal from the RPM sensor. The GM-style sensor is the same as the G4 and they both work in the 80 100, 200, UrS and RS2 cars so you can easily find one at a junkyard or at a parts store. Test them out - put your DMM in resistance mode and measure between pins 1 (with the bump on the connector's side up) and 2 (2nd from the left on the black connector's side). They must be infinite Ohms.
4. ECU
Our 20vt turbo (3B, AAN, ABY and ADU) engines have an ECU that needs to be aware of the speed and position of the crankshaft to make a decision about fuel injector timing etc. In order to do this it uses a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If either of these go bad you will get codes on the diagnostic scanner that could cause engine shut down.
A malfunctioning G28 sensor could result in an inaccurate speed counter for your gearbox or a gearbox that shifts more quickly than normal, and/or an unfire when in the gear. It is likely that the sensor is failing and requires to be replaced if you notice any of these signs. The good news is they are quite affordable more info and readily available, especially when you're looking at the Bosch unit which is what we have. Alternatively, the GM version of this component is also a good option.
5. Tachometer
A faulty engine speed sensor could be the cause of a slew of problems in your car. It's a vital component of the Audi's transmission since it relays information to the ECU about how fast or slow the vehicle's crankshaft is rotating. If this sensor fails, it could affect the performance of the transmission as well as the other car's components.
The G5 engine speed sensor is located at the outside of the transmission just above the flywheel ring gear. It sends a signal directly to the ECU at pin T55/49, via an uncolored wire. The ECU is then able to process this signal to regulate the flow of fuel, timig and boost, and also click here sends it on to the G5 tachometer in the instrument cluster. You can check for sensor failure by checking continuity from the sensor to the tachometer. Additionally, you can verify continuity between pin here T55/49 of the ECU and pin T6a/1 of the instrument cluster (trace [79]), and between pin T6a/1 as well as click here pin T26a/12. It should show around 1000 ohms of resistance between those points. This is a typical part that is found across the Audi 80, 100 200, UrS and RS2 range from 1985 MC until the 1997 UrS AAN and 1995 RS2 ADU so good ones could be available in wrecking yards.