Hey, new guy with a question. I searched the old posts but didn't find a clear answer to my question. Here's what I've got - greatly appreciate any input.

94' sedan, 1.5 w/ 5spd ~ 210k miles. I've put about 105k on the car, noticed that the speedometer is slightly off now from when I got it. I normally set the cruise at 75MPH, at first car seemed to turn about 2900 RPM, now it seems like the speedo is off ~ 3-4 MPH (registering faster then I'm going). Seems like going about 78 MPH and turning ~ 3200 RPM seems to truely be 75 MPH. Can the speedo be recalibrated? One post said no, then other suggested it so it is unclear as to if it can be done. I'd presume so due to the multitude of aftermarket wheel/tire combos out there - I'd doubt that no one runs a correct speedo. I've entertained the idea that I could be getting a slight clutch slip which is causing the higher RPMs, but not where the speed sensor gets it's reading that may or may not be a potential cause for the slight MPH miss reading.

Thanks for any input.

 

do you have aftermarket wheels tires? the speedo can be recalibrated...but im not sure if its electronic or uses a gear in the tranny....if you clutch was slipping going that fast....i think that the clutch would just be fried after a while....also, are your tires getting low on tread? i heard that can make it off just a little like if you have 65 series tires...and they go bald, they might cause the speedo to be off by 1-2 mph...maybey more.

I would take it to the dealership (expensive) or a really good mechanic (prolly not as expensive..but prolly not as able to trobleshoot the problem either) if you really cant find the problem, and are worried about the 3 mph off, buy a new gauge cluster...

 

Stock tires for now. Am going to replace the stock 14s with some Integra 15s. Tire size will be slightly different. Yea a few MPH isn't THAT big of a deal, but I'd like it to be as accurate as possible. Wasn't sure if it could be calabrated like an aftermarket Autometer or VDO guage.

 

i dont think your '94 can be re calibrated like your thinking... now this next question i ask, not to be a jerk, i'm serious, if your tach is reading higher, and your spedo is reading higher, dont you think that its possable that your going faster? how are you comparing and getting your 3mph difference? surely you cant feel 3mph diff at 70+ if anything i would question the speed control, if its vacume driven, perhaps the bellows is getting old and stiff, or maby theres a vac leak, or any # of other things...

i recently thought my spedo was off by 4-5mph, i clocked it against my wifes car... well when i questioned it, i took off on I-10 from san antonio towards houstin... when i started i reset my trip while setting on the side of the road with the passenger mirror even with a mile marker.. after 100+ miles, the error was just a few feet... theres no way, NO WAY that a couple feet over 100 miles can account for 4-5mph. now im smart enough to know that thoes mile markers arent the end all be all of measurements, some are a little short and some are a little long due to exits and whatnot.. but over 100 miles, a few feet.. thats close enough for me....

so now i know that its more likely that my wifes car is the one with the error, and i know that it can for sure be recal'd, so, thats the next project(well when mine dont come first)