Speedometer

We had 2 coils and spark plugs replaced - 70 miles later our speedometer went wacko.   Registers 80 and our gps says 60.  I know I wasn’t going 80!  What would cause this and can I fix it myself.

Janey (resting and relaxing at Lake Point SP  in Eufala, Alabama)

Speedometer is connected to the transmission (physically or electronicly) and has nothing to do with spark plugs or coils.  I suspect (but don't know) in 2014 it's all electronic, meaning the error is in either the vehicle engine/drive train computer or the speedometer itself.  Especially since it was "70 miles later" from the ignition fix before the speedometer whacked out.

That would indicate the need for a trained mechanic with a diagnostic computer to locate the error.

Out of curiosity, does the tachometer also seem to read high?

We’re leaving sat am and will check then.  The motor was running great.
The engine light is not on.

J

I believe the speedometer is not rotating-cable-controlled, but rather electronically controlled.  Before running to a mechanic, I would disconnect all batteries and leave it rest for an hour, then reconnect.  It's like rebooting your home computer.  Maybe you will get lucky and it clears it's head.

Well, I’ll be @#$&!    Left campground this am and it’s fine!    I’m thinking this little Moho has a mind of her own and loves to play tricks!

Janey (happy and content at a brewery in Alabaster,Alabama- Harvest Hosts)