Radio interference

[rick]

E240 Elegance estate w reg
There's a ticking sound on the radio, one tick per crankshaft rev. If it was 3 per rev I'd say it was all ignitions, if it was one every 2 revs I'd say it was one ignition.
A portable radio also picks it up at a range of several metres.
I did have an ignition fault a couple of months ago with HT lead short (bad design in my view) which meant a tow-in, and I'm keen to avoid that again.

Any idea what's doing this anyone?

 

[Spike]

Just wonder if your spark plugs are of the correct surpressed type and that they are all healthy?

If it effects a portable radio then its definately something on the ignition side.

 

[rick]

Mechanic at Exeter couldn't find the fault. Fixed it myself, used oscilloscope to find faulty HT lead.