How to Replace an [[http://ezproxy.cityu.edu.hk/login?url=https://writeablog.net/geminisack40/the-history-of-audi-a1-key|programming audi key]] G28 Engine Speed Sensor

In this video Charles the Humble Mechanic demonstrates how to replace the G28 engine speed sensor. The sensor is situated near the edges of the transmission just above the flywheel ring gear. It transmits a signal to the ECU via a grey wire T55/49, then to the tachometer located on the instrument cluster.

1. Engine Speed Sensor

The sensor is located at the edge of the transmission, above the flywheel ring gear, the G28 Engine Speed Sensor sends a signal to ECU pin T55/49 using an uncolored wire. The ECU utilizes this information to regulate fuel and boost. It also sends a signal to the G5 tachometer in the instrument cluster.

The sensor serves as a reference point to connect with the G40 Camshaft Position Sensor. The ecu has to know when the crankshaft reached TDC, and where the camshaft lies to trigger the spark and injectors.

If this sensor fails when it fails, the ECU will display an error code P00160. This indicates that the Crank Shaft is out of sync with the Intake Camshaft. It could also be a sign of an issue with the chain or a jumped chain link in the upper chain of timing. The code won't appear without the additional information provided by other sensors (G4 or G40).

Testing can be a bit difficult as there are two different pins for the connector  [[https://maps.google.com.sa/url?q=https://olivesweets42.bravejournal.net/the-main-problem-with-audi-tt-key-and-how-you-can-solve-it|replacement audi a3 key]] and they have different functions however the best method of testing it is by measuring resistance between the sensor and the ECU. It should read approximately 1000 ohms when the sensor is in full operation. Examine for signs of coolant, or oil in the connector bay if there are issues with this part.

2. Injectors

Yesterday, while accelerating at full speed from the highway paytoll i had a big cut in power as if the engine was running out of gas or injectors aren't firing any more. I pulled out the spark plugs this morning, three were soaked in gasoline, and the 4th was dry. I put tissue over each injector hole, and when i start the engine without sparks, the ones with gazoline jump right out. The fourth one remains closed. I tested the ground connection of ECU pins 14,30 and 48/55. I got zero ohm. I'm assuming that the issue is elsewhere.

I also tried to reset the PID without success. The [[https://wtools.biz/user/mittenrelish03/|car key replacement audi]] can start if the G28 is not plugged in and it runs perfectly when it is connected, but still has intermittent misfire issues at higher RPM. The coolant sensor (G62) even if it is not plugged in, shows a temperature of -49c. Also i noticed that the gauge for oil pressure in the cockpit is showing 2 bar when the actual pressure is 0.0 when I crank up the engine.

I don't know what to do. I believe that I've ruled everything else out. But i'm worried that I may have missed something. Please let me know If you have any suggestions! TIA!

3. Fuel Pump

The fuel pump of the g28 receives a signal from 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 in a local parts store. Test them out by putting your DMM in resistance mode and measure between pins 1 (with the bump on the connector's 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 decisions about timing of the fuel injector, for example. It makes use of a Crank Position Sensor G4 and an Engine Speed Sensor G28 to accomplish this. If either of these go wrong, you will receive codes on the diagnostic scanner that can lead to engine shutdown.

A malfunctioning G28 sensor could cause an inaccurate speed counter for your gearbox, a gearbox that shifts more quickly than normal, or an unfire when in the gear. It is probable that the sensor is failing and needs to be replaced if you experience any of these symptoms. They're inexpensive and easy to locate particularly in the case of a Bosch unit like ours. Alternatively, GM's version of this part would be an option.

5. Tachometer

A faulty engine speed sensor could be the reason behind numerous issues with your car. It is an important part of the transmission of your [[https://minecraftcommand.science/profile/massthrill68|Audi q5 key]], as it transmits information to the ECU regarding how fast or slow the engine is spinning. If this sensor fails, it can disrupt the performance of the transmission as well as the rest of the [[https://zenwriting.net/doublepimple48/15-surprising-stats-about-audi-a4-key-replacement|audi car key]]'s components.

(Image: [[https://g28carkeys.co.uk/wp-content/uploads/2023/10/woman-showing-the-car-keys-2022-12-16-22-09-32-utc-min-scaled.jpg|https://g28carkeys.co.uk/wp-content/uploads/2023/10/woman-showing-the-car-keys-2022-12-16-22-09-32-utc-min-scaled.jpg]])The G5 engine sensor is located near the edge of the transmission, over the flywheel ring. It sends signals via gray wire to ECU pin T55/49. The ECU then processes this signal to regulate fuel, timig, and boost, and also transmitting it to the G5 tachometer inside the instrument cluster. You can test 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 as well as pin T26a/12. You should detect the resistance to be around 1000 ohms between these two points. This part is common across the [[https://www.tanzlife.co.tz/author/rodson84/|audi replacement key]] 80-100-200-RS2 series, starting from the 1985 MC all the way up to the 1997 UrS An and 1995 RS2 Du So, you may find good ones in wrecking yards.(Image: [[https://g28carkeys.co.uk/wp-content/uploads/2023/10/Mercedes-Benz-3D-Star.png|https://g28carkeys.co.uk/wp-content/uploads/2023/10/Mercedes-Benz-3D-Star.png]])