i just got a 97 f150 5.4 4wd the tach goes to 0 when i turn the truck off. as soon as i start it it jumps up to 2500 and sticks there. any idea what is going on here?

 

Has the instument panel ever been removed?

 

does it change at all or what? Did you buy it knowing this flaw?

 

im not sure if its been removed prior to me. yes i did buy it knowing it. not a huge deal i wouldnt think. i did wiggle some of the wires and it acted normal. but i could not get it to recreate normal activity while driving. and i only got it to act normal once. now i put my tuner on it, and when it winds first out say 4500+ now the tach will drop to zero and then back up to 2500??