[ICOM] Help needed with noise on HF in the mobile

[Randy]

Des:
In general, these days the recommendations for most any vehicle are:
Start by grounding, with some braid, the tailpipe, both near the engine
and at the back end.  Then use braid to ground the hood, trunk (or
hatchback) and doors.  That is about all you can do with modern vehicles
but should help quite a bit.  If you have a hash noise it is often the
electric fuel pump, whose motors apparently use designs based on old
spark transmitters(!).  A ferrite filter in the power lead, located as
close to the pump as possible, should help if you have that problem
(some people do and some don't).  After you have done all that you will
probably be about as good as you are going to get.

de Randy, W7HR