135is speedometer reading 2-3mph higher

[inevitab1e]

Speedometer has always read a couple MPH higher than actual speed. OEM wheels, OEM tire specs. Tried the JB4 settings and didn't make a difference.

Anyone know what could cause this and how to remedy?

[MightyMouseTech]

Originally Posted by inevitab1e

Speedometer has always read a couple MPH higher than actual speed. OEM wheels, OEM tire specs. Tried the JB4 settings and didn't make a difference.

Anyone know what could cause this and how to remedy?

Normal. All cars are like this.

You can code your car to turn on the digital speedo and have it show uncorrected speed, which is actual speed.

[kb2wji]

my 128 speedo is way high (2-4mph) also - it's annoying. All this time I thought I was making real progress - nope.

[SoFloE82]

I've found its not padded by a MPH value, but a percentage value it seems. In other words when the speedo is at 15 MPH I'm probably going 14 or 13MPH. But when the speedo is at 100 MPH I'm probably closer to 95 MPH. I run a mirror tapped 9500xi that I have set to display speed when it's not receiving a signal so I use that to gauge true speed.