$187...............................that sounds cheap? for alota work. i had something similar happen, and it wasnt that cheap to fix more like $0000's
i posted this in the past about it...
i have just experienced the same issues with my cooling system on the 175 allotec vz. one night in traffic the temp gauge and thermos went nuts a few times (in slow traffic),pulled over and the engine was quite cool ????? i got back on freewaY and everything went back to normal, temperature etc.(there was no loss of permformance may i add) when i got home,there was no coolant..and white goo on the oil cap, way more than just condensation.took the car to the mech the next day and 2480 dollars later ALL the gaskets, oring at the front, in the cooling system, changed.heads removed and sent away for crack test, maching etc. they came back good thankfully,total engine flush and water pump was gone as well. 5 leaks during preesure test.it was like a fountain (i changed thermostat while i was having work done, to costly if it fails as well later on). even though i looked after my car well, and had it serviced when needed,check oil and water every week, i wasnt flushing the system enough, and probs not using the most suitable coolant for the alloytec . the coolant turns slighty acidic after 12 or so mths and eats everything slowly. the wrong coolant is , from what i hear and read, the cause of most premeture cooling system failures......
spose its a little like a human, not enough good liquid in it and it will slowly die....