OK so I have a 2002 Audi A4 1.8T quattro. While the car is idleing you can feel it vibrate. The tach on the RPM is right at 800 RPMs. The vibration is obviously the worst in gear so I feel it whenever I am sitting at a stop light and tends to be worse the colder it is outside. I know that the spark plugs were changed less then a year ago and the motor only has 50,000 miles on it so I don't think a timing belt needs to be changed yet. Any ideas? I looked around on the internet and found some thoughts for it possibley being the throttle body. I took the tubbing off and with a ear swab took some throttle body cleaner and cleaned some of the gunk off. ( don't worry i was very careful not to mess with the flap). Let me know. Thanks in advance

 

mine does the same thing but it is a 3.0 it idles rough but rpm's stay put

 

I have a 2004 A4 1.8T with the same issue. 55K miles. The vibration is worst when idling cold and gets better after completely warming up but still more then normal. I had the seller change the engine mount which did not fix the issue before I bought the car.

I have researched and there is some history that the issue may be the cam chain tensioner not working properly. Since this is a major project to replace and I don't know how to test it I have not attempted to replace this part.

The only other thing I have found is the long term fuel trim is around 10-12% on Vag Com block 32. I have run some fuel injector cleaners (Seafoam and Techron) thinking the injectors are not balanced well and some of the cylinders are running lean. This did not seem to make much of a difference.

Let me know if you figure anything out.

 

called audi today and the tech who i trust with anything said that almost 9 times out of ten its an engine coil getting ready to go bad. He said though that it wasn't worth my time and money to find it because its literally impossible to find. So he just said to wait it out. I am going to check the MAF sensor which i also found out can be some source of the problem.

 

You can ohm out the coils after it starts to idle funny. The coil with 0 resistance or the one that has extremely high resistance is at fault. You should be able to find the acceptable ranges online.
On the other hand you could buy a new coil, maybe 2, 3, 4 who knows, if they haven't been changed yet the rest are soon to follow throw them in your trunk and....wait.

 

can you tell me exactly how to ohm them out.

the only other thing too is...i'm not sure if its the coil because the car doesn't stall or sputter and there are not any check engine lights on. Now it could mean that a coil is going south but i'm still not sure. The vibration has worsened some and now even does it when its warm outside

 

The vibration is caused because you have a loose front axle.
Check it out with someone in the car jacked up shifting from "D" to "R" and one with a flashlight checking the axle play.

 

i'm curious as to what made you say that because I have had the driver front cv axle changed but it was reman.
Today it was 68 degress in the mountains of va and the car was much better so i've gone from coil to motor mount and now i'm leaning back at coil again because of the temperature variants. But still no idea

 

i dont know a lot about cars, but i know that ive had a lot of problems with the vacuum check valves. whenever a check valve breaks my car idles really rough and the rpms go up and down when im idleing. if you are having a problem with rough idleing i would look at the check valves, thats what the problem always is on mine, i hate those things!

 

If your car idles ok (without fluctuations) in Park but vibrates excessively when you put it in Drive or Rev . Another sign is, if the car gives you a little knock when accelerating from Stop and you hear a clicking noise....check the axle. I think your case is different as you get bad vibrations when driving.