90 Si Hatch

YES i have searched and read everything you can possible read. but for some reason my heat will not get Hot. the temperature gauge will read normal and i can even feel the lines on the back of the heater core from inside the car and they are hot.

but i can turn on the blower to high (4) and it will blow almost hot air for about 30 seconds, then go Luke warm. then i turn it off for 30 seconds and back on and just repeat the same thing over and over....

i have read other threads, on which way all the valves should be. but could someone please help me go over this again!

the car is a 1990 Civic Si

spoolinfool

iTrader: (1)

You have a fat air bubble in your heat core. It need major bleeding.

Datunnerkid

Yup yup. Or you're heater core fins can be clogged with crud. So u r getting air but no heat through it. U would never believe the things I've pulled out of heater in the way of the heater core

Datunnerkid

Yup yup, or check if there's anything inside the heater box blocking the heater core so u gots no air flow.

gsrekrevs210k

ive been having a problem similar to this one

does that year civic use 2 cables? one from the heat selector switch to a white plastic piece on the bottom of the heater box and then somehow connected (cant explain very well)by another cable to the valve in the engine bay? i broke one of the plastic pieces on mine that somehow controls the heater box vent door and now it swings back and forth. i get open vent(heat) on hard take offs and if i stop quick it slams shut and my heat will go straight to cold. sometimes it goes in between and is warm. if i have the blower on 4, it stays open(heat), but when its at 1 or 2, it sometimes gets slightly closed and becomes warm

i would post pictures to better show you but i dont think im able to on here yet because im a "newby" lol

hope this helps