I was pretty surprised. The difference was striking.
Even after the CB was hardwired and the antenna was grounded the readings were bad. In fact they were actually worse. We keyed the mic and had the SWR readings shoot into the red where that wasn't a problem before.
Oddly enough while Matt was adjusting the antenna I noticed the reading would plunge to fantastic as the tip of the antenna got close to the roof... maybe it was reflecting off the body??? I dunno.
We sat in the garage for awhile, I set myself on fire, and then we figured we'd go ahead and uncoil the cable. So we cut the zip ties and uncoiled the wire that was neatly wrapped in a loop under the dash.
The first test we left it uncoiled in the street. Our readings instantly got fantastic.
The second test had us looping it in a clumsy figure eight, again the readings were fantastic. Unchanged from uncoiled.
The third test we stuffed it up under the dash. We figured it was a possibility that maybe the wires under the dash were causing interference. Still the readings remained consistent with the uncoiled results.
Like many on here I was skeptical that the coiled cable could be a problem. But I'm a very firm believer now.
Cliff notes...
Figure 8s seem good, unwound cable seem good, circular coils are bad.