Throttle doesn't work

Engine Performance problem
2005 Ford Mustang V8 Two Wheel Drive Automatic 31,000 miles

When accelerating from a stop in my 05 Mustang GT the car suddenly jerks forward. The only way to describe it is that as you push in the gas peddle it takes further then normal to go and then it leaps forward. Like it skips straight to around 3,000 RPMs. What could the problem be?

Thanks for the advice but it turns out it was just a dirty throttle body thankfully. The only reason I found this out was because of me putting a new intake on.

I changed the oil in the car now the car wont but hardly start and has a lot of grinding noises when it does. It also has no power. If it dioes get running it is grinding and squeaking and has zero power

Engine Performance problem
2005 Ford Mustang V8 Two Wheel Drive Manual 18000 miles

My Mustang GT, 2005, has low mileage and was running on a two day trip just perfectly and giving me over 24 mpg, then I stopped at my destination.
The next time I started the car, about two hours later, I noticed the trip meter was reset to zero and then the message center displayed the "Failsafe Engine Mode" message and the car idled OK but wouldn't respond to the accelerator. The gauges read fine and no other message lights or warning lights came on. I limped it two miles to my destination. The next morning, it started and ran fine with no messages and no "Failsafe Engine Mode" warning. I drove it about 15 miles and all seems to be fine. What do I do next? Will it hurt to drive the car? In five days I need to drive it 1200 miles to my home and work location and I am not trusting it. What if it does this at 70 mph in the middle of nowhere in Alabama? Thanks.