Speedo reading approx 20mph too fast
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Speedo reading approx 20mph too fast
Hi everyone, just got a four door saloon, and noticed speedo really fluctuates and looks 15v- 20mph too fast. Any ideas. The car is original 1098cc with, I thought, no modifications.
Re: Speedo reading approx 20mph too fast
Sort out the 'fluctuations'by withdrawing the inner cable and cleaning/lightly greasing it - but not the last 2" at the speedo head. What 'tpm' number is shown on the speedo face??



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- Minor Legend
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Re: Speedo reading approx 20mph too fast
Speedos were allowed to be 10% optimistic but not allowed, by law, to under-indicate.
Perhaps the speedo indicator needle needs repositioning, if it is reading approx 20mph when stationary? Fluctuations, as mentioned by another poster, are most likely down to the cable drive from box to head. May even require replacement, if badly worn/damaged.
Perhaps the speedo indicator needle needs repositioning, if it is reading approx 20mph when stationary? Fluctuations, as mentioned by another poster, are most likely down to the cable drive from box to head. May even require replacement, if badly worn/damaged.
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- Minor Addict
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Re: Speedo reading approx 20mph too fast
Is your odometer working?
Sometimes instability of the needle is caused by the odometer drums being stiff or jammed. If lubricating or replacing the cable doesn't fix the needle bounce, the speedo will need a full overhaul--or just replace it with a good one.
Don
Sometimes instability of the needle is caused by the odometer drums being stiff or jammed. If lubricating or replacing the cable doesn't fix the needle bounce, the speedo will need a full overhaul--or just replace it with a good one.
Don
Re: Speedo reading approx 20mph too fast
Possibly it has a changed gearbox, diff, wheels or tyres.
Re: Speedo reading approx 20mph too fast
Thanks to everyone, just for info,
the odometer is working alright, and the needle rests at about 10mph when engine switched off.
The speedo has the following reference SN4423/04 then a space and 1408 printed on it.
I will investigate and try some of the suggestions, hope to post back soon, wife's illness may prevent for a while.
the odometer is working alright, and the needle rests at about 10mph when engine switched off.
The speedo has the following reference SN4423/04 then a space and 1408 printed on it.
I will investigate and try some of the suggestions, hope to post back soon, wife's illness may prevent for a while.
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- Minor Addict
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- Joined: Sun Feb 01, 2009 6:24 am
- Location: New South Wales, Australia
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Re: Speedo reading approx 20mph too fast
Sorry to hear of your wife's illness.
It looks like the over-reading can be corrected by repositioning the needle as suggested above. I can give instructions if you want to do it yourself.
Don
It looks like the over-reading can be corrected by repositioning the needle as suggested above. I can give instructions if you want to do it yourself.
Don
Re: Speedo reading approx 20mph too fast
TPM is fine then -as above - you need to reset the needle to zero.


