04 545i doesn't accelerate like before

BEFORE (2plus years ago)

Pre-purchase test drive 545i at my dealer,
-car was a Rocket out of the gate.
-Very smooth acceleration and deceleration (at any speed)
- Car would accelerate quickly on the touch of the pedal without in DS
- Was a thrill and adrenelaine rush

Now

- Going 50 on the freeway,very heavey pulling ahead of others unless put it in DS
- The transmission is not as responsive in gearing down or even reacting.
Driving style: is aggressive.

Dealer says it drives like any other similar 04 545i, but I don't buy that. Maintenance has been done at the dealer as per schedule.

What additional things can I do to get performance back? Is it natural for performance to decline with Age on a BMW?

Well that isn't normal that is for sure with the way your explaining it.

Can you explain more about the transmission being not as responsive. Is it not kicking down properly? Is it kicking down but the get up and go seems gone?

How does the car react on simple hard acceleration off the line up to about 60 or so. Getting in the 4.5K plus RPM range.

It gears down but doesnt accelerate quickly, the engine also sounds noisy.

Also, alot of times, the gas pedal isnt responsive, theres a delay in power. By that time if you need to pass the car coming from behind its already too late.

0-60 its not as peppy as it used to be, clicking quickly and firmly. The throttle is not as repsonsive.

Usually when you test drive a car they let you test drive with 1/8 tank of gas left. I too had that experience. I'm sure with a few performance mods it would be like driving with 1/8 tank of gas with a full tank.

After pouring 2 bottles of engine zMax into the crankcase and 1 into the gas tank after a few days it drives way better than before. I couldn't even hear the engine going to church yesterday with the heater off and radio off. I looked down and was at 45 mph, looked in the mirror and everyone was 10 car lengths behind. I didn't floor it, I wasn't in DS mode, I wasn't in semi-auto mode, I was just driving in D with 1/4-1/2 throttle at most.

I'd take it to local independant shop and have them do basically a full tune up on the car and explain what your issues are. You should beable to get this done fairly reasonable. The should swap out your plugs, inspect all your hoses, belts, and vacum lines, replace filters, oil change, etc. etc.. A lot of people have noticed a difference in swapping out there plugs well before the 100K BMW recommends. Plus they can listen to engine and find out if its a mechanical issue.

Quick thing to try (though I'm not sure it will change anything for you) is the transmission reset. Put the key in the 2nd position and hold the gas pedal down for about 25-30 seconds.

Thank you for the replies.

I am going to try out an indpendent tech.