Cannot ground antenna for CB

[Clown]

I posted this topic in the General Discussion forum, but maybe the real experts are here on the radio section...

I bought a Cobra CB for my pilot and wired it up. I bought a Firestick antenna and a metal mounting bracket that I screwed into the frame of the rear hatch so that later I can easily fill in the unobtrusive holes if I sell the car. I measured the SWR to tune the antenna, and found it very very high, indicating a poor ground. I went to a CB shop and the tech agreed that that was the problem. He used his own meter to measure the SWR. The first thing he did was use his own antenna and his radio plugged into one of the "cigar lighter" power outlets, same problem. He used his own connectors, same problem. That eliminated other possibilities. He attached a wire to the mount and tried to find an adequate ground--screw holding the taillight, door latch, trailer hitch, even the bolt which attaches the hitch to the frame of the car--no luck. He gave up and told me to use a magnet mount antenna. I tried moving where I had grounded the radio to a better site, no change. I tried a magnet mount antenna, no change. Somehow, my Pilot won't even provide a suitable groundplane for two way radio through a magnet mount antenna on the roof!

Any ideas? My next thought is to use a "no-groundplane" antenna and special coax cable that Firestik sells for CBs on fiberglass boats, but this is getting expensive and frustrating. Especially when I know that there are volunteer firemen and HAM radio operators with two way radios on this board.

[rocky]

Double posting is frowned on. Please post link to original thread and continue discussion there.
Thanks

[Clown]

My apology for the faux pas. If anyone can shed light on this problem, here is the original post thread:

Cannot ground CB antenna

[mclairmo]

Can always run a wire straight to the battery ground cable or the engine block. That's the best ground you got.

[armandjones82]

Sometimes, you may think of needing to really make things work out like having good antennas installed on your vehicle. In that way, there would be no problems to occur on the succeeding times that you equipped that on your vehicle.