Heater Blower works intermitently

[onerchprk]

I need some help.I have a 1990 Pontiac Bonneville SSE With all the electronic stuff.The question i have is what would make the heater turn on and off when it feels like it.I will start the car one time it will work for a while then the next time it will not work at all....If someone could help it would make my day... Thanks

[radeohedca]

I had a similar problem on my '96 Bonny.
The blower motor would come on or go off or work slower than it should. I originally thought it was an electronic control problem because of the failure mode but I was urged to check the blower more thoroughly. When I removed the old blower, I jumpered power directly to it and it worked fine until I moved it around, then it stopped until I jiggled it again. I replaced it and the new one works perfectly.

[JJ052653]

I am having the same problem with my heater on my 95 Bonneville. Haven't had a chance to replace the fan. What I do when the fan is not working, I raise the hood and tap the motor with a stick and the fan comes on. real Hi-tech. the motor goes for about $ 55.00. I am waiting until warmer weather to replace the fan. The fan motor seems to work when the temp is 45 degress or above.

[onerchprk]

Thanks alot it was the blower motor.I picked it up from AutoZone for $28.99 Thanks for all the help

[Gityerstuff]

Originally Posted by onerchprk

Thanks alot it was the blower motor.I picked it up from AutoZone for $28.99 Thanks for all the help

- did you replace the motor from underneath the hood on the firewall ? I need to replace mine too, but thought I would have to take the dash off. Does it remove and install easily ? thanks.

[randman1]

The blower motor is removed/installed from under the hood at the firewall. There's one electrical connector and about 5-6 small screws. Sometimes it takes a little fussing to get it out from between the blower box and valve cover but it does come out without removing any other parts.

[bobof15c]

I had same 96 Bonne SE intermittent heater/ac blower motor problem and purchased new one for $46, started replacement of my new motor and fan. However, when I took the bad unit out the plastic motor cover (part number 52-468-407) fell apart into about 5 pieces. Here's the weird thing--several pix I have seen in AF of Bonne firewalls show the blower motors without a cover..? Is it even necessary to replace the cover or should I just press on without it? I looked the part number up on some GM Parts web sites and ... nothing!

Update -- Used the old rubber gasket and got thicker washers so I could use the old screws. Worked great so far!!