car runs ruff ,no power and will back fire when cold. after 3 or 4 min. of driving the car will scream. I HAVE 114,000 miles on sensors 500 on rebuild. had problem before rebuild. put trick flow elbow on, stock elbow had tear.

 

Try cleaning your Mass Air Flow sensor and see what happens.

 

I always let my car warm up for 6-7 minutes and run it soft for another 5 so i have no idea if it would have this problem. I would guess the car is not getting enough air until the car warms, so a sensor is probably dirty or bad. I know my A4 shifts funny and it seems to be lacking full power until it is good and warm.

 

Replaced cap and rotor? It should be changed at 100k miles, if you haven't that might be your problem. I had a similar problem, ruff and no power, changed opti spark cap n' rotor, problem solved.

 

Check the coolant temp sensor.

 

Totaly agree with Injuneer. I would check that first.