Speedo problems

[CEF33Y]

Hey ppl, i got some issues with the speedo in my ceffy. It seems to be out by aroung 20 km/h at 100, like i'm doin 100 but it says im doin 120. it seems to get progressivly further out, like at 60 it says im doin 70 and at 160, well the speedo is off the clock, and the speed limiter still hasn't cut in. at first i thought i had a lower diff ratio, but that doesn't explain the different variations. Also when I accelerate slowly the needle goes round smooth, but if i boot it the needle jumps 20 km/h at a time, like from 140 straight to 160. Anyone have any ideas???

[mongor]

the speedo could be out because you have different wheels than what came on it from factory.. there for i think you will need to re-calibrate it somehow or get a transformer to plug into the back of the cluster.

[C_DawG]

Mine is the same mate, it seems like the needle sticks in places and it is way off. I have stock diff.

I use an RSM for speed, it was checked with a GPS and is quite accurate.

[CEF33Y]

Thanks for the input, i can pretty accuratly stick to the speed limit, cause i know what rpm i need to be doin in a certain gear, still bloddy annoying though

[nissaner]

same problem here... (also the km readings are higher by around 20%, ie. clocks 1.2kms every 1km i travel... will be - factor when i sell the car)

in my case, the problem most definately is the small tyres that came with the car as my mechanical-minded friend told me (read sky80y) the tyres on the car atm are 195/55/15s... i'm getting 205/60/15s soon...

[CEF33Y]

205/60/15 are what i run, i thought my tires were to big, but if they were too big i'd be goin faster than what my speedy said, just on a side note, nissaner, do you go to the off street drift at oran park?

[BasketCase]

I think your needle is toast, I replaced my speedo because that happened to me, I have an aftermarket diff and 18"s on mine and my new speedo is only 5km/h out. When im doing 100 speedo reads 95. I got that information courtesy of a dyno

[CEF33Y]

hmmm might look round for another speedo then, thanks dude

[nissaner]

205/60/15 are what i run, i thought my tires were to big, but if they were too big i'd be goin faster than what my speedy said, just on a side note, nissaner, do you go to the off street drift at oran park?

hmm... maybe the problem wasn't my tyres...

and no i'm yet to goto those drift meets in my ceffy... public streets are challenging enough for novice drivers like myself...

[OneNonly]

Hmm, sounds like a common issue. I bought my Cef in QLD and sat on the speed limit all the way back to ACT and had some very abusive trucks behind me :S Haven't got around to comparing speeds to my Camry but feels about 10kms out at 70, 15 at 100 etc.. :S

[Slain]

yeah mines the same, figured it was because of the 2 way diff?

[CEF33Y]

I think i'll go to a instrumentation place see if he can sort it out, by the sounds of it its fairly common. The speedo is cable driven yeah? does it have any electronic input? cause the g/f's pulsar q's tacho does the same jumping thing

[adrnln]

I have been told also that they Ceffys have a common fault with Speedo cables breaking as I have been through 2 so far. ( have a few (4) coming from jap in the next container)

Also the sensor in the G/box has been know to do the jumpy thing in speed as it does it with my ARC-R

Will follow this up when it all arrives

[summoner]

I found my speedo was out by about 5-10 kmh but I also ran differant size rims. Also as been said by adrnln it can skip/jump as well as break(mines been broken for over a year). I'm thinking of fitting a digital sender unit and my RSM finally so I have a working speedo

[adrnln]

I have also found that no Speedo effects everything. My idle, My fuel consumsion, boost, even abs??????????

Its messed up

[aKTiVE]

My friend had this problem, and it was because he was running an MX5 Gearbox in his car (which is from a Holden VL Commodore).

This will cause the speed to be 20kmh out... maybe it doesnt apply to you guys, but i thought i should mention it.

[oz_cefiro]

my cef does the same thing with the speedo, i.e doin 100km/h on speedo but only doing 85km/h on the road. But mine has stock size rims/tires, i.e 195/60 15in. But i have a locked diff aftermarket manual conversion.

By the sounds of it this is a common problem.

David

[Oosh]

My speedo is consistantly 10% higher than what I'm actually doing, I base this on the speed reported by my Impakt DigiDash (takes it's data from the diagnostic port) and other traffic.

The needle also "floats" if you know what i mean, it just doesn't seem to move right and wobbles a bit back and forth from time to time, I have a feeling it might be the cable where it hooks up the back or gearbox isn't quite right but have yet to check it out.

[SideWaysChef]

I seem to be having the same problem with my cheffy. I just picked it up at Freo port today an it seems to be out around 10-15km at 60km/h. I know it has been converted from auto to manual, maybe they didnt get the manual sheepo cord.?

that is all I can think it might be as putting on bigger rims shouldnt change affect the speedo that much.

[kursed]

theres a ceffy speedo cluster on ebay right now.