91 firebird tbi 350

replaced heater foil tube going to air cleaner, replaced theromstat, and the fan is not wired hot.
my car can sit for 20 min and not warm up and i can drive across town and it wont warm up. it just takes forever what could be some problems?? ideas whould be greatly thanked

 

Not warmed up as in a high idle engine running cold, or not warmed up as in temp guage stays low and no heat coming from vents?

 

the temp on the gauge dont move and i dont get heat for 30 mins or so when i think it should be warmed up in 10 min

 

Bad thermostat.

 

replaced it in theory that it was the problem yet sadly thats not the case

 

Just because it is new, does not necessarily imply that it is good...... On one particular car I used to own, I got into the habit of buying THREE thermostats, to save myself trips back to the parts store, cause sure as god made little green apples, two of them would be bad.

Pull the thermostat, see if it is stuck open, verify what temp it opens at.

 

umm... well i understand i guess ill give it a shot and see... it cant hurt id just never had a bad part before
ill post back if that is or not the problem yet more ideas will be good.

 

If it's not the thermostat - maybe the heater diverter valve is stuck or not getting enough vacuum to move the valve. That could cause you to have plenty of warm coolant circulating, yet it never comes into the heater core to be felt in the cabin. And you may just have a bum guage or bad temp sending unit. The guage sendig unit should be on driver side head between #1 and #3 plugs.