diesel question

  1. #1
    hi got a mat at work wants me to look at his car no his diesel car takes ages for the plug light to go off and usually goes off quick why is this happen so far changed his plugs and this still happens ???? is there out else its been taking 5 mins for them to heat up some times
  2. #2
    faulty relay.bad earth
  3. #3
    this happened to mums car.... battery was dying and eventualy died was goin to change the glow plugs but changed the battery first, started first time