Seemingly random while driving 40 ~ 50 mph the speedometer will occasionally jump up about 5mph and settle back down without the RPMs increasing along with what the speedometer is reading. Not tachometer, the speedometer. No stepping on the gas to go faster or taking foot off the gas to slow down, just while holding it steady cruising along.
If it was tachometer I'd think maybe the ECU (as I had that issue on the '93 mitsu I have) but I have no clue what could be causing this. Is this an automatic transmission related issue? Or is there a sensor or cable or something I should check? Really lost! Admit it's only been about 2 hours total of driving time so far since I got it so not sure if it always does this or not.
I can't find anything about this in the book & forum searches only gave me more things to do on other lists, lol.
Anyone have this happen before? What was it? Or could it be?
Wasn't sure what topic to put this in, hope it's okay here, thank you.