[cswa]

When I got my '99 Rodeo three years ago I had a faulty speedometer and fuel gauge (still have a faulty fuel gauge). Speedometer and odometer would stop functioning, so I pulled the dash and put in a 'verified working' gauge cluster from ebay. But this doesn't have the same symptoms or issues it seems, so I wouldn't start throwing parts at it.

It seems like you may have an issue potentially with voltage though - If multiple electrical systems are acting up sporadically, I'd start looking at the battery, how old is it, have you verified the charge on it?
It seems partially like your Alternator is working when generating enough power but it may not be at low rpm and should also be checked.

Rain seems to make it worse

Rain or using your wipers? I think the extra load from the wipers could contribute to the lack of electric power.

 

[cswa]

It very well could be a grounding issue. That's a good point I'll have to look around and check some crap out. But I think I might not have explained it as accurate as possible because the blinkers being sped up is the only thing that happens at idle. All the other things happening are at speed. It can be on smooth roads or bumpy roads makes no difference or 1k rpm or 5k rpm. Thanks again for the input and I'll see about tracking down some grounding issues.

While Occam's Razor is usually the best way to think of a problem, (multiple symptoms attributed to 1 problem would tend to be 1 solution) it may be a grounding issue in conjunction with another electrical issue revealing a bad part like the alternator. I'm not sure myself but is there a diagram floating around for where the grounding points in the cabin & firewall are? That would be a good way to check the immediate grounds for your dash.