ok, I have this problem for a while now... 95 VTEC Prelude H22A1 with 215/40/17 tires
I think this problem started to happen after I got my clutch (ACT) replaced with this mechanic... I know he does good work and all but it was my first time delt with him, now the problem is...

my speedo is off... reading shows faster at 0-50mph (but i'm actually below that speed) and reading shows slower at 50+ mph (ie. on highways when it says 75 but I'm actually going 85mph [tested many times with friends to verify]). Basically the speedo works just fine, it increase and decrease logically... it just giving out wrong speeds....grrr
so basically i've been driving by the RPM guage for quite a few months now... tire size isnt the problem here, I've been using these wheels 17" and tires 215/40 many many many years (6+years)


I heard there's a speed sensor at the transmission up in the engine bay and there should be a speed gear too... but i'm not sure where it is and if i can take it out and have a look and fix/replace it because of my wrong speed reading problem... it's getting annoying

hmm you think he might have put it back wrong or it's just old and broke or what? also what needs to be done to get this fixed for a DIY?

 

It's a slight PITA to get to, however you can try a new speed sensor to see if it clears up. Since you're getting a consistent reading, it shouldn't be a bad connection (you would get no/intermittent reading with that situation).

 

so i guess nobody really knows...

 

why not take it to a speedometer shop to get it checked out ... i wouldnt think that changing the clutch would cause this problem sence all he probally did was disconnect it then connect it back again ....