'97 Bravada Heating prob

[rachmarie]

My bravada's heating has become tempermental. The heat will go on only sometimes. The A/C is not effected and it as well as the heater still blow, just what comes out of the heater is not warm. Could this be the heater core? Or is it something worse?

[Chris Stewart]

Do you have to drive a long time before the heater will blow out warm/hot air?

[drdd]

yup, probably heater core ...

to replace the heater core you need to remove the whole dashboard - so ...

I'd recommend doing this first ...


go to Autozone and buy a Prestone reverse-flush kit ($12 or so) and a Prestone acid flush ($10 - comes in a two-sided can - one part acid, one part nuetralizer), and a Stant brand radiator cap ($10).

Install the flush kit (easy).

Follow the acid flush directions ...

... proceed to reverse-flush the hell out of your cooling system.

... check that your rad-cap-to-overflow tank hose is not plugged ...

... change your rad-cap to the Stant brand cap (ACDelco's from the factory are defective and allow air into the system causing Dexcool to react with air and create Dex-crud)

... I saved my 97's heater core by doing this. It took two SERIOUS flushes though ...

Originally Posted by rachmarie

My bravada's heating has become tempermental. The heat will go on only sometimes. The A/C is not effected and it as well as the heater still blow, just what comes out of the heater is not warm. Could this be the heater core? Or is it something worse?

[rachmarie]

No matter how far I drive the air that is blown out is still cold, although it is not ice cube cold. A flush is a good idea. Any idea how much it will cost to just get the core replaced if I take it to a mechanics? Unfortunatly I live in an apartment complex and can't really work on my car like I would prefer to do, so a flush is out for me. Thank you though, I will keep that in mind if this ever happens again.

[Chris Stewart]

Is the coolant tank up to the full mark when the engine is at normal running temperature? Mine was low once and the heater quit working.
Does your Bravada have Climate Control...with temperature in degrees on the temperature knob or the manual knob with the blue/red indicator stripe?

[rachmarie]

I lifted the hood today an noticed that the coolent reservoir was bone dry. I took it to the mechanics and they said the antifreeze turned to the consistensy of oatmeal and that it was commen for GM product to have this prob. The radiator cap was shot too. A good flush got everything back on track and I have heat now (although for some reason the heat was working when I got to the mechanics) . I also know now not to use the 100,000 mile antifreeze that GM recomends. However the mechanic said that the car lagged when it shifts gears, and that would be something I needed to address the next time I came in for any reason. I am not familiar with what that could be except a transmission problem. Any ideas? Thanks for all the advice prior to this.

[Chris Stewart]

I had a shift solenoid go bad in mine. $$$

[GunsOfNavarone]

As DRDD posted, I purchased the flush kit (actually two). I was doing temporary duty from home ad did not have access to hozes to flush the system, so I installed two flush kits (on both heater hoses) and then went to a car wash and stuck the high pressure nozzle into the heater hose that went to the firewall and the spayed the dayights out of the heater core. The installed the flush kits and added coolent. It worked! The slooshing sound returned later- so I took of the radiator cap while engine was cold, let the engine heat up, and then had my wife get the engine reving to 3000 rpm while I added coolent. No more slooshing sound and plenty of heat two years later and no heater core replacement.