This has been happening for a while now, when im just driving normal my car will hold back and start shaking until i let off the gas a little then it will stop but then as soon as you start getting comfortable it will do it again, and its not like you can power through it or anything the rpm's wont clime or it wont stop shaking no matter how far you push the gas in, until you finally let off a bit then you can start accelerating again. any ideas of what could be wrong?

 

Boost leak, bad gas, or old plugs

 

What he said ^

 

Same thing happens to me at around 3500rpm in 5th gear. And it makes the check engine light come on. I believe the error code is p0300. There was supposed to be a factory reflash that would fix it. I had it done and it was gone for a week and then came back. Unplugging the batt for 30 min will cure it for a day or two until I hit the freeway. Don't make the mistake of replacing the coils like I did because a "tuner" told me that was the problem. I am going to see if a custom flash will fix it. If you find a different fix please post it. Look up the p0300 code fix and you will find several "solutions" it's very confusing and frustrating. Good luck.