When I accelerate or when going up a hill, the front blower motor quits, des not matter if A/C or heat is one, does it for both. As soon as I let up on the accelerator , it starts blowing again. It doesn't make any strange noises. Any suggestions? I hate to spend $40 to replace it if it won't fix it.

 

Hi Rusty,
I know you know how to do this, but it sure would help if you considered trying it.
We don't know at this point if the circuit is losing power or ground when the blower motor quits, but if you connected your voltmeter and watched which side ,power or ground, is dropping out checking should confirm which one. Last but not least it could be the motor itself. To confirm that you could remove the motor and take it over to the battery and confirm if it operates as it should, thereby by passing the connections to the motor in it's usual place. What do you think?

I hope it is the motor that is quitting and not a vacuum problem affecting one of the air ducts.

 

Need to find some help. Someone to watch the meter while I drive. Won't do it revving up the motor while sitting still. Will a bad resistor do that? Don't think it is vacuum. Those motors are loud on high and it sounds like it just shuts off.

 

Here is something else you can try.,
The blower motor resistor controls all the speeds except hi speed . That is controlled by a high speed relay because the motor draws quite a bit of current and the best way to provide that is through a separate set of relay contacts. If only hi speed is affected, the relay may have a problem, worth checking out..
Again if all selected speeds are affected, I don't believe the resistor would do that. (
A reminder, the circuit is always powered and the switch positions provide the ground.)
After taking care of all the power window problems you fixed, I am confident you can handle this , (A piece of cake !!)

There have been problems with the wiring connections at the blower motor switch. They were known for getting hot, & corroding , then getting hotter until the heat melted the plug and connections at the switch Easy to check and confirm. If you find there is a problem there, I know the dealers had a kit with newer plug and heavier wiring to handle the high load of a blower motor pulling excessive current because the bearings went dry and created high drag on the motor.

 

Thanks, I will start checking. Motor runs fine hooked up direct. Guess I could wire around everything and just run it on high.

 

Checked the connections, they seemed fine. Odd thing is, I drove it around for about 20 minutes at a steady speed and the motor ran fine. But if I accelerate hard, it quits. Soon as I let up on the gas, it blows again.

 

I believe 2 things are happening when you drive the vehicle.
One is the motor will torque when you accelerate and move some and maybe it is moving some wiring..
The other point could be when you depress the accelerator a connection get moved.
So that brings up a check you might try.
With the blower on high speed and the engine not running,, but in Drive ,do you notice any change when you depress the accelerator pedal as if you were accelerating ?
If no change is noticed, I would look for what wires move when the engine moves on it's mounts.
In Park, engine off, hood open, if you try pushing or pulling the vehicle slightly the engine will move some and you might get some idea of where it moves

 

Thanks, I am willing to try anything at this point.