I have a 96 audi a4 quattro

Read your owners manual on how to set or clear your speed warning. There is nothing wrong with your car.
IIRC, the speed warning is zeroed by holding down the left instrument cluster button for more than one second when the vehicle is moving faster than 3mph. The icon will show with a diagonal bar through it indicating the speed warning is turned off.

Get a service manual, it will help you locate it. Usually they are under the hood or behind the glove box.

The brake light issue isn't likely the the brake switch (since it sounds like your other brake lights are working properly). It's likely a bulb in the third brake light. When the filaments get old they sometimes lose and regain contact as the car vibrates on the road. Change the bilbs and see if the problem goes away. If it doesn't, look for a bad wire connection around the third brake light. Also, have someone verify the third brake light isn't working from the back of the car when you see the alert, it could be a bad sensor.

the only thing i can think of as a problem would be brake pad quality. i would get some from the dealer and fit them. if there is chatter going on it can also be caused by low quality rotors or a bad maching job. have them inspected for integrity.

You have to find someone who can hook up a diagnostic computer to your system. The code should tell them what system is giving you the problem, then you have to narrow it down from there. I have a mechanic friend who does this for me so I have a clue of the problem before I go to my Audi dealer. The engine warning light could be any number of things.

audi a4 tdi Emission control system light on dash

I hope that you had the proper weight oil installed, at your oil change. If your oil is up to the proper level, and it's rattling ,this is VERY bad. White smoke usually means steam in the exhaust, and that means a blown head gasket. Check your coolant level. I wouldn't drive it anymore......until someone knowledgeable can diagnose it!!!!!

Silly question: Have you checked the transmission fluid level, and is it to manufacturer's spec?

i had a similar problem with my 97 a4 2.8. i changed my daytime running lights relay and it solved the problem. its located under the steering wheel behind the knee bolster

have the oil pressure checked as soon as you can... also have them check the wiring for the oil sending unit

Robert

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