Ok, so for the most part the previous responses are totally not helpful and quite inane.
Sure, I drive a 318i 1995, it is pretty slow off the line compared to many other cars, but maybe you have a real problem; other than 1) being an auto, and 2) being an auto.
Here's what I would do:
1) Move the gear selector into 1, and then jump on the gas. If you feel the car accelerating better then, you car may not have been starting in 1st, possibly 2nd or even 3rd. Don't forget to shift into 2nd, or stop accelerating before you blow past the red-line.
You can use the A/M switch to toggle between Automatic shift and manual. Under manual, you will need to manually shift the gears with the selector - but don't worry, there is no risk in changing gears at any point in time (regardless if A or M is selected), I frequently drop it into 3rd while decelerating quickly, or if I want to pass someone.
Remember, the gear selector is an UPPER limit while in A mode - it won't go above that gear. And, also, there is a danger of putting it into first if you are going 60mph - but there might be a lock-out safety, but I havenít tested that, for obvious reasons.
2) Check your RPM's when you start, and write them down at different speeds. 2nd will always be about 2000 at 20 mph for example (it may not be, I just made that up) So, if you are going 20 mph, and you are at 1000 rpms that means you are in 3rd gear.
Hope that helps - and remember your 318is - not only looks way cooler than a POS intrepid, but it handles about 1000 times better.
Please let me know how you make out.
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