That's a possibility, but you can do it yourself if you don't mind getting your hands a little dirty. I'm new on the forum and not sure where the mods stand on this, so won't go into any detail here.

Anyway, FWIW, I've only had mine (2001 4.4i Sport) a fortnight but had noticed a surge at about 4k revs a couple of times. I generally drive pretty sedately though so I couldn't tell you if it was doing it every drive. I checked the error codes a few times and there was consistently an error for the cam sensor on bank 1. I bought and fitted two new sensors today and so far, touch wood, no more error codes, and having deliberately run it well past 4k revs a few times there was no surging. The engine actually seemed smoother generally but that could be simple optimism having spent ££££s on a couple of small pieces of plastic

So based on my experience, I'd say you might need new cam sensor(s), but get the codes read before you chuck money at it.

Steve.