Have a 2005 Mercury Montego, on many occasions the engine suddenly surges and the RPM increase. This is dangerous and I quickly have to stomp on the brakes. Happens in both. Drive and reverse. Afraid I will hit someone or something when I pull out of a parking space. Have brought car to dealer 3 times and they say they cannot replicate and checked computer codes and found nothing wrong this is an accident waiting to happen.

- San Marcos, CA, USA

Engine revs up, and car lurches, typically when: - shifting into drive or reverse and/or moving away from idle; - almost always when the wheels are cranked all the way to the left or right and the car is moving away from idle. The lurching is sudden and "violent" enough that it can catch a driver unprepared - my wife and I are used to it and able to compensate, but we aren't letting our 17 year-old drive the car for now unless one of us is with her. Ongoing problem since car was purchased new. This has been an occasional problem for years - complaint was even made while car was still under its 3 year/36,000 mile warranty (nothing found). Problem has been getting more frequent over the past year or so.

- Milwaukee, WI, USA

My 2005 Mercury Montego (79,000mi.) has unexpectedly lurched on two occasions. The first time I was driving slowly in a parking lot, and the car suddenly accelerated and lunged forward. Braking helped, but the lunging occurred again each time I tried to drive forward. I was able to move into a parking space and turn the car off which stopped the lurching movement. I sat for several minutes, restarted the car and drove away without incident. This didn't happen again for several months until a similar occurrence yesterday. This time I was ready to back out af a parking space, put the car in reverse and it surged backward. I depressed the brake, put the car in park, and shut it off. Once again I waited several minutes and drove away without incident. This is a very dangerous situation as people could have been close to the car when it lunged, or I could have been in traffic. I consider this to be a serious safety issue. With both of these occurrences the " fail safe mode" message appeared.

- Mechanicsburg, PA, USA

Car showed "failsafe engine mode" on the display panel and did not respond when I hit the gas almost causing an accident as I attempted to change lanes. Engine response was intermittent after this and then the "wrench" symbol showed up. I pulled into a gas station and turned off the car to try and look at the owner's manual to see what this meant. Could not find details. Turned the car back on and the "wrench" was gone and the "failsafe engine mode" display was no longer showing. Worried this may happen again...

- Allen Park, MI, USA