Testing spark plug wires

[Northy]

Hey all.

I’m trying to test my plug wires.  Google searching suggests 3k ohms is the magic number for a 911SC with Beru leads. 
 

My old set all read about 3.9 - 4.0k ohms.  I have a newer set and most of the leads aren’t registering when I have the meter on 20k ohms. One of them will read 13million ohms. The car starts and drives (albeit with a lumpy off throttle behaviour- what I’m trying to solve), so the leads are ‘working’.  But it seems weird they don’t register when connected to the multimeter. I’m sure I am making a connection.  

Anyone got any suggestions? Is there a better way to test them? 
 

On my old very wires the boot can come off the lead and I can test just the lead too. Not sure the new ones do this, @Type911 any ideas? 

Edited September 19 by Northy

[Type911]

Are the new ones Beru?

[Northy]

Yeah 👍 a few years old, but only been on car a few months.

2 hours ago, Type911 said:

Are the new ones Beru?

 

Edited September 19 by Northy

[Jonny Hart]

You can unscrew the plug end from the lead.  There’s a brass screw in there - sometimes it’s not even in the centre core of the lead.  
 

There are 3 x 1k resistors in the cap.  The  leads themselves are about 1k depending on length.  There’s 5k in the rotor making a total of about 9k which is the design spec for the system from coil to plug. 

Edited September 19 by Jonny Hart

[Type911]

Hoped JH would come up with the full spec, if they are Beru you have have no worries, leads will be fine

[Northy]

3 hours ago, Jonny Hart said:

You can unscrew the plug end from the lead.  There’s a brass screw in there - sometimes it’s not even in the centre core of the lead.  
 

There are 3 x 1k resistors in the cap.  The  leads themselves are about 1k depending on length.  There’s 5k in the rotor making a total of about 9k which is the design spec for the system from coil to plug. 

Thanks @Jonny Hart - very helpful. I’ll unscrew the ends of the leads and test the lines and the caps separately.