wierd tachometer issue

[92bronco_in_progress]

ok, i'll set the stage for you.....i get in my truck to leave from work and everything is working normally, so on my way i home i stopped at my favorite gas station to pay 1.78 a gallon, which i was excited about lol....so i shut the truck off, and the pump clicks off, th guy tightens the cap and hand me my receipt and says have a nice day, as if to jinx me or somthing haha......so i start the truck and now my tach is reading at 2500 RPMs, but the truck is idling normal. so i shut it off.....waited i few seconds, restarted it, same thing....so at this point i was just like f**k it, so i go down the road, and the tach goes up with my RPMs and down when the tranny shifted like normal.....only 2000 RPMs more than it should have read. so what can cause this? and what needs to be replaced to fix it, because i have OCD when it comes to things like this

 

[Seabronc]

All I can tell you is to check out the connections Especially the ground.

Good luck,

>-

 

[92bronco_in_progress]

All I can tell you is to check out the connections Especially the ground.
Good luck,

>-

wanna hear something funny......went out this morning fired her up to warm it up.......and the tach was working fine......went to work......went to lunch......its working like it should now.....must be the 1992 high tech lol

 

[Seabronc]

Great! If it does it again, check the connections for corrosion and tightness.

Good luck,

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