7 Small Changes That Will Make A Huge Difference In Your Audi G28
7 Small Changes That Will Make A Huge Difference In Your Audi G28
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 situated at the edge of transmission, above the flywheel gear. It transmits a signal to the ECU through the grey wire T55/49 and then to the tachometer in the instrument cluster.
1. Engine Speed Sensor
The grey wire is situated on the edge of transmission, directly above the flywheel ring. The sensor transmits signals through the grey wire to pin T55/49. The ECU then uses this information to control the boost, fuel, and timig. It also sends an indicator to the G5 Tachometer located in the instrument cluster.
The sensor is used to link with the G40 Camshaft position Sensor. The ecu needs to know when the crankshaft is TDC and the location of the camshaft so it can start spark and injectors according to the situation.
If this sensor fails the ECU will throw a P00160 code which means the Crank Shaft and Intake Camshaft are out of sync and possibly indicating chain stretch or a jumped link on the upper chain of timing. However, the error code won't be displayed on its own without additional information from other sensors (G4 and G40).
It's a bit tricky to test since there are various connector pins, and each one has different functions. The best way to do it is to measure the resistance between the ECU and the sensor. When the sensor is fully operational, it should be reading about 1000 ohms. Look for signs of coolant, or oil in the connector bay if you have issues with this part.
2. Injectors
Yesterday, while accelerating from the highway paytoll at maximum speed I noticed a massive decrease 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 with gazoline 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 pop out, but the 4th one stays shut. I tested the ground connection of ECU pins 14,30 and 48/55. I found zero ohm. So i assume the problem is somewhere else.
I also tried to reset the PID without success. The car is able to start if the G28 is not plugged in and is running fine when it is plugged in however it is experiencing intermittent misfires at higher RPM. The coolant lost audi key temperature sensor (G62) shows the wrong temp value -49c even when i unplug it. I also noticed that the oil gauge in the cockpit shows 2 bars but the actual pressure is 0.
I'm not sure what to do. I think I've eliminated everything else. However, i'm afraid that i might have missed something. If anyone has suggestions, please share them! TIA!
3. Fuel Pump
The fuel pump on the g28 is activated more info by a signal from the RPM sensor. The GM-style sensor is identical to 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. Testing them is easy to do - just put your DMM get more info in resistance mode and take measurements between pins 1 (with the bump on the connector end 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. It makes use of a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If you encounter a problem with either of these sensors, the diagnostic scanner will display codes that could cause an engine shut down.
A malfunctioning G28 sensor could result in an inaccurate speed counter for the gearbox or a gearbox that shifts faster than normal, and/or a misfire while in gear. If you experience any of these problems, it is likely your sensor is failing and needs replacing. The good news is they are very affordable and easy to find particularly in the case of the Bosch unit like ours. You can also choose the GM version of this part is also a great option.
5. Tachometer
A faulty engine speed sensor could be a cause for a slew of problems in your vehicle. It's a crucial component of the transmission of your Audi since it sends information to the ECU regarding how fast or slow the engine is turning. This sensor could cause the transmission to fail and other components of the car to be affected.
The G5 engine speed sensor is located at the outside of the transmission, above the flywheel ring gear and transmits a signal to the ECU at pin T55/49 through a grey wire. The ECU utilizes this signal to control fuel and boost, and also timig. It also transmits it to the G5 Tachometer in instrument cluster. You can check the sensor for failure by examining more info the continuity between it and the tachometer, between the ECU pin T55/49 and the instrument cluster connection via pin T6a/1 (trace [79]) and between T6a/1 and the instrument cluster pin T26a/12. You should get more info see the resistance to be around 1000 ohms between these points. This part is common across the Audi 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.