[RFI] Diesel "ignition" noise (actually injector solenoids?)

[Richard (Rick) Karlquist (N6RK)]

I rented a diesel truck over the weekend to move a
tower and noticed that the (apparently factory installed)
Delco AM/FM radio was useless on weak signals due to what
sounded like ignition noise.  The noise went away
if I took my foot of the throttle, leading me to
believe that it was caused by fuel injector solenoids
or something like that.  The noise was bad on both AM and
FM, making me wonder if it was via the 12V supply as
opposed to RF.  Is this a common diesel problem or
just typical GM incompetance.

I used to have a diesel VW and it produced no noise
whatsoever on the HF bands.

Rick N6RK