Mine had a flat spot turned out to be the solonoid valve bought a new one from pug for £20 iirc been fine ever since
One way to tell if the solonoid is faulty it to swap the pipes round . Have you got a major flat spot between 3 and 4 k or 6 and 7k? If you do have either, swap the pipes around if a 3k flat spot moves to 6k and vice versa a new one is required.
One way to tell if the solonoid is faulty it to swap the pipes round . Have you got a major flat spot between 3 and 4 k or 6 and 7k? If you do have either, swap the pipes around if a 3k flat spot moves to 6k and vice versa a new one is required.