94 olds climate control blower will not shutoff with ignition off

i will now read the online service manual to you.
https://eautorepair.net/Marketing/Default.asp

blower fan located where. dash heater blower fails
or radiator fans of some odd kind added later.
coolant fan or dash? there are 2 coolant fans and 3 relays to run them and all 3 relays, can fail and coolant fans blow for ever and ever. fuse 6 kills the relay coils. only, so if relay is welded fans blow endlessly. even if bcm is removed from the car.
on the other and the heater blower is 100% controlled by the BCM

so car engine starts and runs and drives ok right.
when did car last run perfectly> , or seen ever ?
service manuals for 88 cars are not easy to find
means real oem manuals, best. 35 years old !
no digital then ,just a huge paper bound book, remember?
holy moly this 88' has a body controller here, bcm , relic amazing thing.
facts: 1988
here is proof

It sounds like you may have a malfunctioning component in your heating system that is causing the fan to continue running even when the car is turned off. Pulling fuse 47, which controls the climate control blower and ignition 3 relay, stopped the fan from running but may have also caused other issues in the system. Replacing the fuse may not fix the problem, it may be necessary to have a mechanic diagnose and repair the specific component causing the issue.

If you have climate control it could be the main processor. Something could be shorting the blower relay to keep it on. You would also need to check and see if the system is still full of freon.

Sounds like your controller is bad. http://www.resistorguide.com/applications/blower-resistor/ <Read this info.
http://www.ebay.com/itm/88-94-GMC-CHEVY-TRUCK-CLIMATE-HEATER-CONTROL-93-92-max-SILVERADO-SUBURBAN-SIERRA-/381127684906

If you have the automatic climate control and the blower motor won't shut off then you have a failing Blower motor speed control module. Something inside this module goes bad and the result is a blower motor that keeps running at times even though the engine is off and the key is out of the ignition. The module isn't repairable but has to be replaced. I believe it is located behind the passenger side of the dash panel.

the blower motor you have must be for the automatic climate control. If so the fan module is at fault keeping the blower motor on

more than likely it is your blower motor resister

replace the blower speed control module located near the blower motor

1996 olds lss .no heat from vents which seem blocked.The fan runs

there is a blower motor control unit under the hood on the right side near the firewall, unplug this and it should stop running. normal problem for a lot of gm cars with electronic climate control