[MikeCStig]

Originally Posted by One Foot

OK. New thermostat. Bleed the system. Still nothing.
I have a question here. How big a bubble would air lock the system? How long will it take for any and all bubbles to be expelled? How do you know if there are any left?

So I read a bit more and I try the recalibration bit. Worked like a charm. Now I have cold air and a code! Yippee!!
Wiper button flashes once followed by 4 flashed of the button just below it (the intermittent wipe button)

Also, the thermostat bypass hose is kinked and I have no idea what condition the bottom end is in as my back is f@€#D and I can't get down there to look.

To answer your first question, it would take a pretty big bubble to completely airlock a cooling system. Think of it this way, it would have to be big enough to occupy a large portion of one of your main radiator hoses, and if you bled the system, that should have sorted it out assuming your water pump and thermostat are functioning properly.

There are 2 things that I would be concerned about. First, the issue you mentioned with the windshield wiper switch and the code which I assume is triggering the check engine light. These are potential signs of an electrical problem, which on a Plymouth voyager ( or a dodge caravan) from that period would not be unusual.

You also mentioned a kinked thermostat bypass hose. That is definitely something that should be addressed, in fact I would look into that first. You may just want to replace that hose because if it's been kinked for too long it's probably damaged and liable to burst at any time. If that doesn't work, I'm sorry to say that you're in for some electrical troubleshooting, but hopefully it's just the hose because that would be a much easier fix. Good luck.