So my Crossfire Coupe Limited accelerates really slowly most days, it feels like i'm driving a 4cyl. I replaced my crankshaft sensor recently and after unplugging the battery and resetting the throttle my car ran like a dream for a few days and there was a dramatic increase in acceleration, after awhile it went back to slow and sluggish unless i'm driving with a HEAVY foot.

This week it's also been very cold here compared to what it normally is and has averaged 15-25degrees. It is now stuttering to crank, it never completely stalls but takes 2 or 3 seconds longer to startup, once the car warms up it will shutoff/crank normally. My car has 70k miles on it and i'm not sure if it's ever had a tune up (I bought it with 56k on it).

Does it sound like a tuneup would fix these issues and if so how much will a tuneup cost? $300-$500? I'm not too car savvy so it's going to the shop for whatever it needs.

 

How old is the battery in your car?
That would be the first thing that most of us on here would recommend that you check and replace.

BC.

 

I'm not sure how old the battery is, I haven't replaced it since i've bought the car so at least over a year.... sometimes when I crank up my car my tail freaks out and will rise on it's own as soon as the car cranks... Could that be related to the battery? Would the battery effect the acceleration problem or only the crank?

 

Check the made by date on the battery. But, as Forum members always note, strange things happen when the battery is going. I just replaced mine this month ---- hopefully to avoid the gremlins from coming out. Seems like yours has a few gremlins working the spoiler when it shouldn't.