No power full throttle above 4500rpm..help!!!!

[bmwdoc5]

I've changed fuel filter, spark plugs, and the distributor cap is new and spark plug wires are new. I tried the "pull the vacuum line off the fpr" and see if there was any difference...and there wasn't. I'm pretty sure I have good vacuum all over. I sprayed brake clean all over the wires and there are no leaks. So, if I'm full throttle and once I get around 4500 to 5000 rpm the motor is screamin but there is just no power at all all the way to redline. I mean seriously, it takes an eternity for the rpms to climb after 4500-5000 rpms. It kinda surges sometimes also. I have no idea. If anyone has noticed this or heard of it before...please let me know. Thanks in advance for your help.

[180fan]

checked out the clutch to see if it's still grabbing at those rpm?

if it's also surging and you've checked for vac leaks and also cleaned up the connections at the electronics (I hope this is what you meant by spraying brake clean over the wires), and done a tune up, you could also be having a situation with 1. the tps, if it's malfunctioning then the ecu would be dumping wrong amounts of fuel to deal with the air in there. 2. is there a temp dependence by any chance?

[VeloceDrift]

I had a similar problem with my KA-T i would be at 7psi but would get beat buy some old lady who didnt even know we were racing It turned out that i had a bad knock sensor. never knew what that was til i found out it was bad, check your ECU codes because as far as i remember it will not trigger the check engine light but it will throw a code if you check. i dont know if its the same with every car but when my motor was ice cold in the morning it would haul *** but after about 5 minutes or so it would do that until it sat all night.