MY s/4 TII bone stock no mods.. here are the probs

int the morning when COLD turn on heater idle drops but only for a sec or two and then goes back up to normal 800 or so

when she is all WARM turn on heater small idle drop, turn on head lights drops same amount then goes up to normal, now if i turn on headlights then she will make putting noise sounds like quiet back fire. and wants to die and idle stay very low...

She drives/idles fine if she is only under one load meaning , either head lights on OR heater cant do both at same time or wants to die..

I put new s/5 TII alternator
bran new plugs
new magnacore wires
battery tested fine

 

On the passenger side of the UIM is the BAC valve. From your decription it sounds like it is adjusted improperly.

By the battery is a green plug that is not connected to anything. This should have only two terminals in it. Use a wire to jumper this connector. This will put a load on the motor. Then move to the screw that is on the BAC valve. You can adjust this to set the idle where you want it whenever a load is on the motor. If you are having problems running more than one thing (heat, lights, ect.) set this valve so the engine idles higher than it would without a load. (around 1000 rpm).

Now remove one end of your jumper wire. See where your rpms are at unloaded idle. plug the jumper back in just to make sure your BAC is working right.

Note: do this when the motor is up to full operating temperature. Also don't forget to remove the jumper when done.

 

thks i try tomorrow.. do i need to adjust it with an ohm meter or what?

 

Nope, you don't need an ohm meter, just hook the jumper up, turn the screw out to raise loaded idle and in for lowering. Set your loaded idle by your tach.

If you want more detail check the FSM found in the FAQ sticky.