Ok well its getting colder here and all last winter I had barely any heat from the same issue, I have no idea what is the issue. When I put the heat on and fan on low it is as hot as I can get it, if I put the fan speed on any higher the air is cold. I've attemped to backflush the heater core but I haven't put any cleaner in there.

The fan works at all speeds.

Car is a 1991 Honda Accord 2 DR LX with 167,000 miles

It is no fun driving with no heat.

 

Could be your thermostat stuck open which is a lot better than being stuck closed. If it's been a while, swap it out with an oem thermostat.

 

Are you sure the temp **** is turning all the way to open up the valve to the core? They are famous for getting sticky. When I installed a new Cd player into my 95 Accord I made sure to lube that up while I had that panel off. Several times It has gotten to the point of when you turn it to full hot or cold it wants to spring back to the middle.

 

Yeah I already changed the thermostat when i replaced the radiator.

The **** does seem to want to sprang back, the only way I even get close to sufficient heat I have to really turn the **** and it clicks otherwise it wants to spring back i'll try to lube that up.

 

My 91 accord does something similar, to get the heat all the way on 'hot', I have to manually reach down and flip the linkage to open the core. get in there and move it back and forward a few times and make sure it has the travel it needs. I think its about 1/4 turn (theoretically- if you could turn it in a complete circle(you cannot))

 

yeah my linkage moves when I turn the **** but the doesn't get real hot like it should it is just luke warm.

 

Ok, could be your water valve located on the firewall. Try manually turning it to open it up.

 

Yep that's the next thing I'd check after you free up that heat **** and make sure it's opening all the way.

 

No the water valve opens up with no problems and the heat **** moves freely now, but still the same issue. The outlet hose from the heater core is not anywhere close to as hot as the inlet, could there be a clog in the heater core?

 

That's possible. There is a youtube vid for cleaning out clogs in the heater. Do a search.