Engine going flat between 3-5k rpm

[johne4]

Greetings

I have a 2000 Boxster with 54,000 miles, last week the engine started running flat between 3-5k rpm, the car accelerates great till 3k rpm, then goes flat, feels like fuel starvation, but when it hits 5k to redline it accelerates normally again.

Since it was close to the 60,000 mile service I went ahead in changed the plugs and air filter. That did not fix the hesitation.

I have not ruled out the possibility of some bad fuel, still got a 1/2 tank to go through before I can rule that out.

Just trowing this out to see if anyone had a similar problem and what the fix was since there are so many possible culprits from a clog fuel filter (on order) to pluged cats.

The check engine light does not come on.

Thanks in advance, any information/help anyone can provide will be greatly appreciated.

John