Having problems with your 1991 GMC S-15 Jimmy ?
Low valume of air out of the heater
\015 The fan is working properly, but there is little valume of air comming out in any direction.\015
I had the same problem with my '93 jimmy....the dealer i got it from had replaced the blower with a counter-clockwise direction fan and it was barely putting any air out of any vent. took out the blower and replaced with one that was clockwise rotation, now it will blow your hat off!.......worth a look...not too hard to remove the blower, just remove the overflow tank and you can get to all the screws holding the blower in.
Does the vents swithc from defront to vent and floor or its it stuck on defrost? if its stuck on defrost then open hood check for broken or cracked vac line to hose on the hood. if it switches then remove the blower resistor and inspect the evap core for clogging if it is clean it to restore the flow of air thru heater system
Repair Help & Product Troubleshooting for 1991 GMC S-15 Jimmy
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