91 loyal will not engage 4 wheel dr.
Check the fises and or relays but sounds to me like the solinoid to engage the 4 wheel drive is either not get power to it or it needs to be replaced
I mean fuses
check your vacuum lines
I do not belieave those were vacum operated I think they were electric then. Don't know for sure though
they were electric, start where ronc258 said if that dosn't work check for power at the solenoid, if you have power there then replace the solenoid.
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