Engine hunting after a long run.

[Lewo]

So, been away for the weekend 150 miles each way, mainly motorway and dual carriageway so had a good run. 
When I stopped at each end the engine was 'hunting'? If I switched off and restarted it after 20 secs or so it seemed to tick over normally. I'll upload the vid later.
I've not been on a long run for a couple on months, my usual driving lately is 6 miles each way and the max has been around 15 miles each way and the engine has been ticking over normally.
My mate did the cam follower the other day and we put a pipercross panel air filter in, I'm thinking the erratic tickover is linked to that but having a quick look under the bonnet the air intake all seems to be connected correctly.
Any ideas? 
Ta

 

[Lewo]

[Lewo]

Any  :ideas?
Will pop round to mates again this wk to ask him to check any recommendations that people suggest.
Cheers.

[Dan_FR]

Can't see the video (in work), but hunting idle could well be an air leak of some description (post MAF sensor), could be PCV beginning to fail.

[richtung]

This happened to my ED30 last month. Turned out to be the PCV failing. I believe the PCV is a common item to fail.

Hope you get it sorted.

Thanks

Rich

[Lewo]

Ah right cheers guys. I know he disconnected a hose from the PCV to make room for removing the fuel pump to do the cam follower so will check for that too.
Going to get a new PCV & DV fitted at Rtech in 3 weeks so assume it's ok to use the car as is until then if we can't find any other faults with the air intake anywhere?
Cheers