01 partner problems

[Sub 1026]

Hi everyone :wave:

I've just bought a 01 partner van and with it a few problems, very slow to start ( new battery and starter plugs going in as I type). When it does start not a lot works only oil light on dash, no wipers, no radio, no heaters, no indicators however if I bring the revs up to 2200 all these start to work. Dash lights brighter brake/ door open oil battery light come on as normal and go off as normal.

Can't figure out where to start looking for this problem. Any advice would be helpfully. :brickwall:

It's a 01 partner with a straight diesel engine, think its a dw7 filter on top with4 screws and the air filter down near wheel

Thanks for reading
Brian