Crazy Rad. Fan

Ok guys I have been trying to figure this one out for a long time. I only have 1 radiator fan, the ac fan is out. Now the fan only seems to cut on when it wants to, most of the time when the car gets to operating temps it will cut on. Well today it decided that it didn't want to cut on so the car started to overheat, I cut the ac on and the fan cut on, when I cut the ac off the fan went off. I cut the car off and the coolant was boiling. Let it cool down some and cranked it back up. This time when the car got warm the fan cut on but after a few minutes it turned off and started overheating again. Drove it around the block and it wanted to run hot when ever I was idleing. Got home and the fan cut back on and worked fine.

I have no idea what could cause this, maybe a bad coolant temp sensor?

Good Lord, are we the only ones plagued with this running hot mess? What's the temp your showing on the logger? Do you have the fans wired together on the relays? Thats how I have, and when the ac is turned on, they both come on. When the coolant temp reaches 205 they both cut on.

I recently made some shrouding out of sheet metal that I got from Lowes. It seemed to help a good bit. However when i took it on the highway at 100+ outside temps, my max coolant temp got to 115 as opposed to 120+ without the shrouding. This is even with the thermostat taken out.

I've done everything possible besides a new Koyo or Fluidyne. This is my next step. If that doesn't work the condenser is getting pulled.