Pug 306, 1.4, tick over and breather pipes

[Skyedriver]

Hi, hoping someone here can assist a friend of mine.
He has been running a W plate 306 (1.4petrol) for two years without any trouble, but recently the tickover has become erratic, sometimes staying high when you lift off the throttle. Cleaned the stepper motor; no change. Took it to an old fashioned mechanic who looked at the breather system and declared it "bodged". The has been a hole drilled in the rocker cover and a pipe inserted. This is "T-ed" into the breather pipes feeding into the inlet manifold after the throttle. Disconnecting and plugging this pipe stops the high tick over but the car now stalls.
Questions - has anyone a copy of a Haynes type manual detailing the correct breather pipe arrangement and has anyone any bright ideas why this "bodge" has been done and the causes of the tick over problem?
Apparently the air filter case is collecting oil, presumably from the rocker cover but as this connects in AFTER the butterfly I'm not sure how it is getting there. Also with the pipe connected, there is apparently so much suction that with the engine running the oil filler in un removable.
Thanks everyone
Tony H

[Uberloin]

Unless you know what you are doing I would strongly advise taking the car to a peugeot specialist. Ultimately it may cost you less time and money, particularly if you exacerbate this type of illusive problem. Hayne's manuals are great for taking you through maintenance tasks but it sounds to me like someone has previously messed about with the car and a haynes manual will not account for this unorthodox modification in its troubleshooting section.

I would expect you'll need a new rocker cover, breather pipes and gasket. good luck.