Coolant flushes & leak stops

forgotmyname

The sale speil is that the stop leak hardens when it contacts oxygen but there is oxygen in the water already

so eventually it's going to find a dark corner of the cooling system and set hard which may block a cooling channel.

Some cars have fairly narrow cooling passages and they can block easily.  Honda V6 engines were one of those they

said NEVER use the stop leak stuff on them it will block the channels.

B0bbyEwing

Mildly_Miffed said:

Modern coolant gauges lie. They are ECU run, and only tell you if the coolant is too cool, about right (a fairly wide range), or too hot. No more, no less. Any numbers marked on the gauge are purely cosmetic. You can see the exact temperature via diagnostics, though, or a cheap IR thermometer.

Would the readings via an OBD2 port bluetooth thingymajig & an appropriate app be more reliable or just as unreliable as the gauge in front of me?

FYI - they tallied, within a couple degree of each other.