Have No Heat

[XtreMeCamAro]

If anyone can help I have been working on my buddys 1994 Trans AM 5.7L, I thought that his thermostat was stuck open so I changed it. Now he has little more heat than before but my question is what else can be causing his car not to have heat, and also when he accelerates he loses his heat..........Please Help
Things done so far: New Thermostat, New Radiator,Coolant 50/50 mix Air was bleeded out of system
I swear this os [img]graemlins/bs.gif[/img] and i am :mad:

[EyeOutThere]

Could have a clogged heater core.

Is he having cooling problems?

[apiccola]

Check the vacuum driven components on your AC system.

[stagen]

Flush the radiator. When you changed the stat you got air in the system. flush and bleed the system.

[XtreMeCamAro]

ok i have flushed the radiator system got all the air out and he is not having any problems with the cooling system, what else can it be ??
it starting to get cold in chicago please help

[apiccola]

Seriously, check the vacuum controlled side of the hvac system. There is a door in the duct system that is usually moved by a vacuum controlled actuator. This door determines whether or not air passes through the heater core. You may have a dry rotted fitting that is seeping vacuum, and the actuator/door may not be functioning correctly.

[jamie]

whats the temp on the stat? if its a low temp stat, it could take a lot longer to heat up...

[rockotman]

<blockquote>quote:</font><hr>Originally posted by apiccola:
Seriously, check the vacuum controlled side of the hvac system. There is a door in the duct system that is usually moved by a vacuum controlled actuator. This door determines whether or not air passes through the heater core. You may have a dry rotted fitting that is seeping vacuum, and the actuator/door may not be functioning correctly.<hr></blockquote>I'm with appacola on this one - I have seen it happen many times - the air is not properly directed because the doors are not being fully actuated. The most likely location for a vacuum leak that will cause this type of problem: in the lines to or from the vacuum reservior. GM uses very thin, stiff, spagetti line. It can be replaces with the regular rubber line; the fitting match.