2001 V70XC - VIDA DiCE is useless...

Post by **JDS60R** » 26 Jan 2015, 10:31

A sharp knock that only occurs before the engine starting and then "never" occurs while running can be caused by a failing coil pack . As it continues to fail it is usually accompanied by an unexplained slightly rough idle or an occasional jerk while driving. Then the coil pack finally fails and a misfire will indicate its position. It can also be a fractured or bad spark plug .

Post by **xHeart** » 23 Feb 2015, 07:55

JDS60R wrote:A sharp knock that only occurs before the engine starting and then "never" occurs while running can be caused by a failing coil pack . As it continues to fail it is usually accompanied by an unexplained slightly rough idle or an occasional jerk while driving. Then the coil pack finally fails and a misfire will indicate its position. It can also be a fractured or bad spark plug .

The metal-to-metal was present this morning before the start.
All 5 ignition coils were replaced in September 2014, and the spark plugs are close to 2 years -- Ignition Coil IPD HD , and Volvo spark plugs, respectively.