Take A Look At Your Fellow Audi G28 Enthusiasts. Steve Jobs Of The Audi G28 Industry
Take A Look At Your Fellow Audi G28 Enthusiasts. Steve Jobs Of The Audi G28 Industry
Blog Article
How to Replace an Audi G28 Engine Speed Sensor
Charles the Humble Technician teaches how to replace the G28 Engine Speed Sensor. The sensor is situated at the top of the transmission above the flywheel ring gear. It sends a message to the ECU through the grey wire T55/49 and then to the tachometer in 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 signals to ECU pin T55/49 using the grey wire. The ECU utilizes this information to regulate boost and fuel. It also sends an alert to the G5 Tachometer located in the instrument cluster.
The sensor serves as a reference point to connect 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 accordingly.
If this sensor fails the ECU will show a P00160 code which means the Crank Shaft and Intake Camshaft aren't in sync and possibly indicating the chain stretching or a jump link on the upper chain of timing. The code will not appear without the additional information provided by other sensors (G4 or G40).
It can be a bit difficult to test since there are several pins on the connector, and each one has different functions. The most effective method to test it is to measure the resistance between the ECU and the sensor. If the sensor is functional, it should read approximately 1000 ohms. Examine for signs of coolant, or oil in the connector bay if you have issues with this part.
2. Injectors
Yesterday, as i was accelerating off the highway paytoll at a high speed I noticed a massive drop in power. It was like the engine had run out of gas. Or my injectors weren't firing. I pulled out the spark plugs this morning, 3 were drenched in gasoline and the 4th was dry. When i crank the engine without sparks, I put a piece of tissue on the top of each of the injector holes and the 3 drenched with gazoline pop out, but the 4th one stays closed. I tested the ground connection on ECU pins 14/55,30/55 and 48/55 i get zero Ohm. I'm assuming the issue is somewhere else.
I also tried to reset the PID but with no luck. The car can start if the G28 is disconnected and it runs perfectly when it is plugged in but it still has intermittent misfire issues at higher RPM. The temperature sensor for the coolant (G62) shows the wrong temp value that is -49c even after unplugging it. I also noticed that the gauge for oil pressure in the cockpit is showing 2 bar when the actual pressure is 0.0 if i crank up the engine.
I'm not sure what to do, but i feel i have pretty much eliminated everything else. I'm concerned that i may have missed something. If anyone has any suggestions, please let me know! TIA!
3. Fuel Pump
The fuel pump on the g28 is activated by a signal from the RPM sensor. The GM-style sender is identical to 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 salvage yard or in a local parts store. It is easy to test them - just switch your DMM into resistance mode and test the distance between pins 1 and 2 (with the bump at the connector's end facing upwards). They must be infinite Ohms.
4. ECU
Our 20vt turbo (3B, AAN, ABY and ADU) engines have an ECU that must be aware of the speed and position of the crankshaft to make decisions regarding timing of the fuel injectors, etc. It makes use of a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If either of these more info goes badly, you will see codes on the diagnostic scanner which could cause engine shut down.
A failing G28 sensor could cause an inaccurate speed counter for your gearbox or a gearbox that shifts more quickly than normal, or a misfire while in the gear. If you experience any of these issues it is most likely that your sensor is failing and should be replaced. They are cheap and easy-to-find, especially when they're an Bosch unit like ours. Alternately, GM's version this part would be an option.
5. Tachometer
A get more info malfunctioning engine website sensor can cause a myriad of issues in your vehicle. It's a vital component of the Audi's transmission since it relays information to the ECU about how fast or slow the car's crankshaft is spinning. If the sensor fails, it could disrupt the performance of the transmission as well as the other car's components.
The read more G5 engine speed sensor is situated on 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 then uses and processes the signal to control fuel, timig and boost and then sends it on to the G5 tachometer inside the instrument cluster. You can test the sensor for any failure by checking the continuity here between it and the tachometer. You can also check continuity between ECU pin T55/49 and the instrument cluster connection on pin T6a/1 (trace [79trace [79]) and between pin T6a/1 and the instrument cluster pin T26a/12. There should be a resistance of approximately 1000 ohms in these areas. This is a common feature across the Audi 80-100-200-RS2 model, ranging from the 1985 MC all the way up to the 1997 UrS AN and the 1995 RS2 Du, so you might find them in wrecking yards.