The car is experiencing unintended acceleration, usually, but not always, after heavy acceleration. Over 10 occurrences. Cannot remedy by pulling back the accelerator. Car must be turned off and the engine must record 0 RPM to remedy the problem.

- Port Matilda, PA, USA

1999 Audi A4 2.8. third time the car needs to replace leaking cam seals on engine. All cam seal repairs completed by original dealer repair dept. First repair was only at 39,000 miles and 6 months off of warranty, in November 2003. 2nd repair was only two years and 30,000 miles later, at 69,000 miles, in February 2005. 3rd repair now needed, only after 35,000 miles later, at 105,000 miles. I have read that this is an ongoing problem with the A4 model manufactured over the course of several years, including 1999, and that the cam seals should last much longer than 35,000 miles. Audi corporate refused to assist with expenses with the 2nd repair. I am in discussions with Audi corporate about the expenses for the 3rd repair. Since this is a persistent problem with my vehicle, and as I've read, many other 1999 A4S, I encourage the NHTSA to research this cam seal engine defect, and issue a defect recall. I had submitted the same request several years ago, when the first incident occurred. Thank you. Karen blumenfeld

- Summit, NJ, USA

A4 timing belt failure in 1998 quatro models.

- Ringwood, NJ, USA

Rapid and catastrophic failure of water pump disrupted timing chain and led to severe damage to engine, requiring its replacement. This incident occurred while I was driving at night on a limited access road without shoulders. I needed to go several hundred yards, at most, to pull off road for safety. Audi's 3-year warranty had expired, and so it offered no help, despite low mileage and regular maintenance of the car.

- Washington, DC, USA

After starting the vehicle a fire broke out inside the engine compartment. Dealership was notified, but did not resolve the problem.

- Desoto, TX, USA

Leaking water pump caused timing belt to fail causing $8500 engine damage on a 1999 Audi A4 with only 28K miles.

- Greenville, NC, USA

When the car was about a year old, the entire airbag system had to be replaced, the repair facility noted to me that I was lucky to bring it in when I did, as it was at risk for spontaneous deployment. Additional problems included an oil pump failure ($750) at about the three year mark; and occasional sudden lurching/RPM revving or sudden onset of a 'lag' in power, which the dealer noted when I brought it in but could do nothing about. I have also had problems with the fuel indicator gauge being grossly inaccurate - indicating I have used only a quarter tank of fuel to drive 350 miles. However, the most bothersome ongoing problem is four or five trips to the dealer to repair a non-functioning cruise control system. Each time they have 'replaced the vacuum hoses' but this 'repair' will begin to fail again later that same day. The system will either fail to engage altogether, or it will be engaged during highway driving, then within a few minutes, the speed will continually decrease until I have to manually disengage the system and turn it off. I reported this to Audi of America's corporate customer service (very friendly and helpful) who helped me arrange another service visit, but the problem has never been resolved. Cruise control has never worked and I'm giving up on it ever working. I just have to pretend that I don't have it, which is very annoying during highway travel.

- Charlotte, NC, USA