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Do we need to change that Long Life Coolant anyway?

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 #395147  by codybryce
long time lurker, first time posting. felt the need to report my success in unclogging heater core in 2001 w/ 225k mi. which almost didn't happen...
was given this 300m Jan 2023 after it had been in an accident. have no records to how it was maintained but judging by the condition of the timing belt and general underhood appearance I decided to through all the basics. ended up replacing belts, hoses, radiator, thermostat, water pump, plugs, wires, all fluids, rims/tires a door and a most of the interior.
long story short. very little heat blowing despite my aggressive flush of cooling system. no errors from atc self check. engine temperature cycles perfect. but little heat inside and if not for heated seats...
side note: thanks to ya'll here, I watched out for the thermostats with reversed piddle valve and sure enough I almost installed one.
so today I clamped off the heater hoses. put clear hoses on and ran the garden hose. ran boiling water through it. poured in some Prestone flush and let it soak. agitated and soak. about an hour in all. more garden hose both directions but effluent remained clear. bummer. used compressed air to help push through distilled water rinses. the last rinse I hit it hard with the air figuring the unclamped hose would pop off but it didn't. instead the other hose turned dark from the crud burst of the clog. woo hoo. more rinse. re assembled, top off and I now have lotsa heat.
now I just need to fix my P0172 issues. trip computer says dte 300 mi but only goes 215. fuel pressure holds so optimistically doubt leaking injector (I did a dyi refurb on them earlier too and they seemed to be okay).
sorry so long, and my finger is getting hoarse anyway.
best regards
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 #395151  by FIREM
Welcome and good to hear of your success!!
Expensive shop tool but air assisted pulse is the best method of flush. ... h-tool.pdf