91 chevy wiper motor problem

[73chevytruck]

i just took the carb motor out of my truck and put a 88 chevy 350 tbi in it with the wiring harness and computer in it and now my wipers only work on high and the park circut dont work neither, i bought a new pulse board and it still only works on high, any ideas? and it work fine before with the old hacked up wiring harness.

[old school truck dude]

Sounds like bad ground.. However, most the time ya end up just puttin a whole wiper motor in these, they aint worth if ya ask me, none of them last in these 90's trucks, must be design flaw - Ive put several in mine 

[73chevytruck]

ill check the ground out and , wipers worked fine before i swith motors and wiring harness,

[old school truck dude]

There are several grounds on the harness. Sometimes the ring terminal on them is corroded where the wire goes in it.

[Kyle]

there were a couple different designs for wiper motors found on these trucks. i had issues with mine (i have a 92) where i thought i had a bad wire cuz it would work then just stop, id wiggle the harness and itd start working again or id just beat on the motor box and itd work.... id just find a newer one outta the junkyard (anything up to 98 should work) and try that first. if u hooked ur harness up correctly it shouldnt be the harness cuz thats what it originally had. good luck!

[old school truck dude]

They wont shut off sometimes, then work fine, then wont turn on.. Had 1 that ya had to shut the key off to make it stop, replaced the whole motor and it was fine each time.. Smh but I think it has to do with the board in there and the connectors