V12 sparking issues
Thread Starter
|
Junior Member
Joined: Feb 2019
Posts: 8
Likes: 0
From: berkshire
V12 sparking issues
Hi
i need your knowledge re v12 5.3 facelift
i have very bad misfire on a bank rev counter has stopped working. I have removed the plugs on A bank or badly fouled with un burned fuel also I get no spark when I test .
so before I push out on parts what is at fault the coil or ignition module top of rad .
new plugs will be ordered NGK
please help with above
best reg
i need your knowledge re v12 5.3 facelift
i have very bad misfire on a bank rev counter has stopped working. I have removed the plugs on A bank or badly fouled with un burned fuel also I get no spark when I test .
so before I push out on parts what is at fault the coil or ignition module top of rad .
new plugs will be ordered NGK
please help with above
best reg
Veteran Member
Joined: Mar 2008
Posts: 25,528
Likes: 11,721
From: Pacific Northwest USA
Could be either.
Or a problem with distributor rotor.
https://www.jaguarforums.com/forum/x...isfire-214228/
Tons of info in the archives. Search under "Marelli failure" or similar.
Cheers
DD
Or a problem with distributor rotor.
https://www.jaguarforums.com/forum/x...isfire-214228/
Tons of info in the archives. Search under "Marelli failure" or similar.
Cheers
DD
Veteran Member
Joined: May 2010
Posts: 4,638
Likes: 2,583
From: Vic Australia
To determine if the coil and/or ignition module is at fault do the following
To test ignition module
Swap the plugs on the ignition modules and on the coils. This will run the A bank on the B bank module. When finished put the plugs back where they belong.
To test the coil
Swap the input to the coils and swap the HT leads to the distributor. This will run A bank on the B bank coil. Put everything back where they belong.
If the A bank still has no spark with either of these tests then the problem is in the distributor.
Pull the dissy cap and remove the rotor, check the rotor for scortching inside and out. Check the inside of the dissy cap the terminals that touch the rotor should be in good condition. The Upper A bank has a pin and the lower B bank had a ring. Check these for condition.
Once you have fixed the problem remove all 12 plugs and replace them.
To test ignition module
Swap the plugs on the ignition modules and on the coils. This will run the A bank on the B bank module. When finished put the plugs back where they belong.
To test the coil
Swap the input to the coils and swap the HT leads to the distributor. This will run A bank on the B bank coil. Put everything back where they belong.
If the A bank still has no spark with either of these tests then the problem is in the distributor.
Pull the dissy cap and remove the rotor, check the rotor for scortching inside and out. Check the inside of the dissy cap the terminals that touch the rotor should be in good condition. The Upper A bank has a pin and the lower B bank had a ring. Check these for condition.
Once you have fixed the problem remove all 12 plugs and replace them.
Thread
Thread Starter
Forum
Replies
Last Post
Shelby676
XJ40 ( XJ81 )
4
Jun 6, 2011 09:15 PM
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)