I retired to Philippines and bought a 2003 350Z, said to be an original LHD, not a converted RHD car. Anyway the speedometer only starts reading after I seem to be doing 10-15 mph, the car has a US mph as the predominate display and with small kph numbers. Seems to get closer to what I think is real as I approach 100 kph/62 mph and higher. Its got 18" Track wheels on it instead of the stock 17"s. I have read the other posts about the rear sensors, ABS or something as the speed pickup device and that tire size diameter affects up to what 10% error?. No flamers, this is just seat of pants and looking out the window. Its just way too slow, lazy to work.

 

Does the trip computer have a speedometer as one of its options? You can cycle through the options by pressing the button on the right side of the cowl over the speedometer. At least that's the case on my '08.

If you find the speed readout on the trip computer, is it different from the speedometer itself? FWIW, mine have always agreed very closely.

If you have a cell phone or tablet with a GPS, you can get an app for a GPS speedometer. Google Play Store has several free ones. They're very accurate, and you can use that to check your vehicle speed readouts.

 

Welcome- you've undoubtedly got a problem with your speedo. But it's not a common problem for the Z33 and whether it's the gauge itself or something else, there's no way to tell without a physical inspection. As winchman says, check your digital speed reading on the multi-function gauge to see if it's getting an accurate signal.

 

Could be it wasn't the original one

 

I've read the posts. I don't have a smart phone or a GPS, or a tablet, gadget dinosaur I guess. Could be not the original speedo, tires size difference between 245 45 18 and 235 50 17 is insignificant. If I were to get a GPS with the correct sampling rate, can someone suggest a brand/model, I can Amazon one over here in minimal time. Any other thoughts?? I have to be my own mechanic for these type things the nearest Nissan dealer with capability is far far away.

 

soo did you compare the speed on the car's trip computer yet? that should be done before you consider buying GPS first.

 

^^Agreed- that's three of us who've made the same suggestion. OP- do you understand what we're talking about with the digital speedo readout?

 

I read your comments on the trip computer, haven't done it yet. I am down, for all things, a serpentine drive belt. I have one flying over somewhere, not delivered yet.

When I am running again I will check the speedo against the trip computer as you all suggested. I will report back, thanks.

 

Replaced the belt, no more squeal. A very expensive belt.

The trip computer mph is not the same as the speedo. The trip computer and my visual/seat of the pants seem to be right on, the speed is 12 mph slow, that is, carefully watching this time, 12 mph before needle deflection. But it seems to be closer faster I get. Observational data only. I also jacked up the back and made visual inspection of the ABS sensors. They are there and hook up to another connector, all intact. So, next suggestion. I so hate electrical/electronics.

 

I'd say the problem is in the analog speedometer display itself. You can download a service manual for free to get instructions for troubleshooting and replacement.

I keep the trip computer set to speed readout all the time, and I hardly ever look at the regular speedometer. In fact, I made a magnifier to set in front of the readout so I can read it better.



I've since replaced that one with a sleeker version. That was the "proof of concept" quickie made out of a plastic cap from a spray paint can. There's a fresnel lens inside to enlarge the image.

 

How much could the accessory belt cost in the Phillipines? Here in Colorado they're $32, last time I replaced mine at 60K. As for your speedo problem, you might need to have an experienced tech take apart your three gauge pod to determine if your speedo has a mechanical problem. Worse yet, your odo might not be the original one, so your miles might not be accurate.

 

The belt, overnighted because not avail where I am at out in the province, was nearly $100.

The speedo may not be the original, still it is slow but the trip computer speedo seems to be right one.