We'll, now that the fuel system on my '90 is sorted, the coolant system wants attention.

Yesterday the coolant light started blinking. Needle mid-way, rad fan works but wasn't even on (checked function afterwards. Works correctly). Engine at operating temp, but not overheated. Thin bit of coolant on the front lip of the expansion tank (left side of engine, not the overflow). Level in expansion tank looked a little low, just at the min line. Expansion tank looked a little high, just over the max line. No apparent loss of coolant previously.

I know of at least two things that are bad / suspect, but would like opinions on other possibilities.

1) expansion tank cracked. Today, after a short drive, could see coolant emerging from just above the lip on the expansion tank, then dripping onto the header.
2) thin (9mm?) line coming from expansion tank to overflow tank looks suspect, possibly collapsed inside.

Additional questions:
- does it make sense to replace the expansion tank cap, too?
- same deal w/ the level sensor - replace?

Both these items are getting replaced, but would like to know opinions before I continue.

Much thanks :)

john