I've been given a 1997 Mk4 Fiesta 1.25i to learn to drive in. Apart from being a bit shabby on the outside and the central locking not working, she starts, runs and stops OK. However, there is an intermittent erratic idle: engine revs rise and fall slowly, and after taking the foot off the accelerator there is a slight delay before the revs drop. The previous owner has removed the air box assembly and replaced that with a K&N type air filter, so I'm thinking that could be the cause.
I've bought a 2nd hand air cleaner assembly from eBay, and ordered an new filter. Could those who know mind having a look at the pictures attached and let me know if I have the right assembly, if there are any parts missing and what order they are fitted please? A parts diagram would be very helpful if anyone knows if an online version is available. I have a Haynes service manual, but can only find a written description in there. I've worked on motorbikes for many years, and this is my first car.
Thanks in advance,