Runaway idle

[Alan Callery <alan_callery@intalco.com>]

Ever since the flatbed put it's trailer hitch through the intercooler...
that's a story in itself ... we've been experiencing an idling situation
where periodically the idle spped runs up to 2000-2500 rpm for a bit, calms
down, at the next light it may or may not happen, etc.

Does anyone have an idea where to start looking?    Is there a switch or
connection that needs attention?

Tia,

Alan Callery
87 5KCSTQW  159000 and looing good!