Hey guys. I have a 2001 chev blazer LT 4x4. Got an issue with my speedometer. Usually when cold (-20F). The speedometer needle will slap around or just not do anything for the first 20 min of driving and even then will still act weird. The transmission of course will not shift when this happens. Always thought must be a bad VSS, but sometimes the fuel guage will go right to empty when this happens and put my low fuel light on. Maybe bad ground somewhere? Something wrong in the harness?

Also i did remove my VSS and cleaned it, though it wasnt that dirty, still did not cure the issue. Is there two VSS sensors? Looks like there is one on the side of tailshaft housing and one twards the top?? Or what sensor is which? Thanks alot guys.

 

Back of the drivers side of the block near the knock sensor there's a ground(s), check that. Fuel lines will be in the way of seeing it so try pulling on the wires to see if it's loose.

 

Ok thanks, ill check that out.