Hi Fella's,
Have a problem with my young blokes KJ Laser, it's a 1.6 Manual...problem has only just started after running perfect for the past year.
It is running rough and sounds like an old chaff cutter..it sounds like it is running on 3 cylinders...chugging.. I have cleaned, checked,tested plugs... all work fine.. leads all work fine and I have spark to all 4 cylinders.. I idled the car and removed then reconnected each plug lead one at a time while it was idling and 1,3,2 all made the motor labour and drop dramatically in idle, but no.4 plug lead made no difference to idle when disconnected from motor... Any thoughts? blocked fuel injector to no4 cylinder?..all thoughts appreciated.
Cheers,
Baz

Hi,

Have you done a compression test ? You could have a burnt valve.