it may be somewhat easier to take the air box off if you have big hands like me haha..
Th best way to check for a plugged heater core in my experince is when the car is warm or hot turn your heat on medium blower speed with heat maxed out and touch both hoses if they are both hot you have flow..if one hot one cold its plugged..when i say both hoses i mean the hoses that run to the heater core itself not the radiator hoses

the northstars ive seen with bad head gaskets..they got replaced and like said never run right if they don't crap out a short time after

the cap.you mean the radiator cap? i mean to pressure test the coolant system with a pressure tester to see if there is a leak still

we just did a pressure test and had no issues,,, only thing we both noticed is that my caps gasket is getting old and brittle and a small part is broken off.......
brother in law said it could wait but maybe not, and yeah I knew core hoses.... when we get it up on the rack on saturday thats the plan is to check them for hot/cold...

okay well you can replace the cap it def won't hurt anything....but the whole no heat issue is just so far sounding like something(most likely heater core) is plugged up

I've heard the story of why not take apart a N* to many times from credible sources to ever think of it myself Man. One of the known weak spots in the heating is the actuator motors go way to quickly. Funny to have both fry at the same time, but... Do you have hot water going into and out of the heater core?

changed the thermostat, heat returned but barely....., heater not clogged....

brother in law thought maybe it was an air pocket in the system, only way he knows how to bleed them out in this model is to run the engine with the cap off, anyone know of another way....

heat is intermittent now, and actuators are fine, core flows just fine all hoses hot....

anyone ever had there surge tank crack?

Never heard of the surge tank cracking.... yet. Not an engine prone to airlock like the 3.8. I had 0 problems when I changed my antifreeze. Both hoses hot it'* obvious the core is too. I dunno, possibly the linkage damage from actuator to flap? Your engine temp would be a clear sign of an air gap. It should read right around 200 and stay there.