This is probably the dumbest question to be posted to date, but it involves the speedometer. Having never had a digital speedometer, the "de-accelaration" readings seem a little funky, i.e. it seems to take a while to work it's way back to -0-. Is this normal, or is there something wrong with my speedometer?

Thanks.

 

I don't think so. Everytime I get a new car (which is waaaayy too often), I try to find one of those police radar thingies that tell you how fast you're going. I don't know if they've got these in other cities, but I always try to find one to see the accuracy of the speedo.

EVERY car that I've owned has been a few percentage points off from the reading on the signs....except my S2k.

 

My speedometer ('00) lags behind the actual speed as I bring the car to a stop. That is, it might still read 6 or 8 mph when the car has actually come to a stop. I assumed it was just the nature of the beast.

 

Yeah, the speedo is a little slow updating, and will read a few percent high e.g., ~1mph high at 60, ~3mph high at 100, etc. as verified with GPS.

 

I was on the NSX boards today, and the mentioned that thier tachs read a little high. I think the S2000's tach may read high also, as mine seems to idle around 800-1000.

 

It is easy to check your odometer. Just have a passenger read out your speed from a GPS while you compare. The GPS unit should be very accurate if you can track 4 or more satellites.

Be careful though. I think all "civilian" GPS units are programmed to read no speeds over 200 mph. This is so no one can buy a cheap GPS unit and use it to guide a missle.

Barry

 

Hehe, on a trip to Indiana, I was tracking my progress with my handheld GPS. Well, somewhere along the way it decided that the highest speed I attained was over 250 MPH! And that was in my dad's Jeep Grand Cherokee!!!



I'm not sure when or why it came up with that reading, but when we were actively watching the GPS screen, it seemed spot on.

 

My S2000, with original and new (~2000 highway miles) tires, was MPH-to-MPH identical to my Garmin III+ GPS up to ~125MPH.

As your tires wear, decreasing in diameter, the in-car speedo should become more optomistic. I wouldn't be surprised by a 3% error just from tire wear.

I don't know the fuzzy details of digital speedo's, but could the slow updating be a result of trying to minimize the effect of very minor changes (i.e. flickering between 65 and 66 MPH, when you're really driving at 65.99MPH?).