Speedo inacurate

[v8 animal]

Had this car for less than a week and i have noticed the speedo is not quiet right.
It seems to be accurate at up to 50mph following traffic,above that it is mostly deafently wrong,approx 70 reads 120 and so on.
Has anybody had the same problem i don't know where to start.
Keeping up with traffic on bypass reads up to 140mph
Quiet concerned about pc plod and the extra miles on the clock that im not doing.
Any one help?
Animal

[d stanley]

Possible a problem with the sensor. They are only a few pounds from a dealer (£20?). Does your car have a castelated collar around the prop shaft near the diff.

Changing the sensor might solve the problem. If that doesn't do it then you might need to replace the speedo, which would be expensive.

[Tobs]

I had this problem when i first got my Chim. It was the position of the speedo sensor - It needs to be as close to the trigger wheel / fins as poss without touching. I had to slightly adjust one of the fins one the castellated wheel, as this was touching the sensor when the others weren't. My chim had the sensor above the prop shaft near to the diff - its quite a to get access!

Toby.

[V8 Animal]

d stanley said:

Possible a problem with the sensor. They are only a few pounds from a dealer (£20?). Does your car have a castelated collar around the prop shaft near the diff.

Changing the sensor might solve the problem. If that doesn't do it then you might need to replace the speedo, which would be expensive.

Sorry no idea to new to the car
Animal

[paul (93 Chim)]

Has your car got power steering?
The reason I ask is if the Chimaera hasn't or is an early car the tyres are thinner, the original rear tyre was 225/55ZR16.
This tyre size went out of production so a lot of owners use 225/50ZR16, this is ok but it does alter the speedo timing as it has a smaller circumference.
The best way to correct this is to fit a 245/45ZR16 which will make the tyre circumference the correct size.

Paul

[d stanley]

I suggest you get out and get under. Its all part of the fun.

[V8 Animal]

d stanley said:

I suggest you get out and get under. Its all part of the fun.

Will do at the weekend it's dark when i get home.
Took it out tonight roof off heater on GLAD I BOUGHT IT WHAT A SOUND pedestrians just stop and watch you go buy.
I got that in the westfield did'nt think i would get the same in the tv
Thanks Paul

[tyre_tread]

paul said:

(93 Chim)]Has your car got power steering?
The reason I ask is if the Chimaera hasn't or is an early car the tyres are thinner, the original rear tyre was 225/55ZR16.
This tyre size went out of production so a lot of owners use 225/50ZR16, this is ok but it does alter the speedo timing as it has a smaller circumference.
The best way to correct this is to fit a 245/45ZR16 which will make the tyre circumference the correct size.

Paul

That might give a small but consistent variation but not of the magnitude that V8Animal is talking about.

Edited by tyre_tread on Monday 16th October 09:42

[Wicker Man]

v8 animal said:

Keeping up with traffic on bypass reads up to 140mph

That sounds about right to me!

Have you tried checking it against a GPS system?

[V8 Animal]

Tobs said:

I had this problem when i first got my Chim. It was the position of the speedo sensor - It needs to be as close to the trigger wheel / fins as poss without touching. I had to slightly adjust one of the fins one the castellated wheel, as this was touching the sensor when the others weren't. My chim had the sensor above the prop shaft near to the diff - its quite a to get access!

Toby.

Hi,
Took the wheels off yesterday and found the part.
How the hell do you get to it looks to me that the diff has to come out.
Surley theres a trick??
Anybody attempted this.
I was doing 140 on the M1 yesterday giving her a run guess i was doing 80 decided to go quicker and noticed the speedo went backwards.
Do you still think it's the sensor?
Animal

[Bob the Planner]

Time to replace mine I think as I have a different problem. I was progressing gently with a few of the NEPH drivers yesterday and suddenly the speedo dropped dranatically. I ended up at one point doing 4000rpm in 5th and an indicated 25mph. Later on it sorted itself out but I think I need to look into it.

[Red V8]

Suppose the upside is that it won't half impress people that you take for a spin.... mega street cred

[V8 Animal]

Red V8 said:

Suppose the upside is that it won't half impress people that you take for a spin.... mega street cred

Yeah got me impressed for a bit now very nervous when approching cameras and no cars around to judge speed.
Need this problem sorting quick thinking about taking it to a TVR dealer.
Animal

[sparkythecat]

V8 Animal - You may find this thread helpful.
www.pistonheads.com/gassing/topic.asp?p=1&f=13&t=189131&h=0

[V8 Animal]

sparkythecat said:

V8 Animal - You may find this thread helpful.
www.pistonheads.com/gassing/topic.asp?p=1&f=13&t=189131&h=0

Thread very helpfull thanks.
So it seems a common problem can't help thinking how long this car has had the fault{i have owned it for a week)
Animal

[rsl430]

[pic] [URL=http://good-times.webshots.com/photo/][/URL] [/pic]

I snapped this with my mobile phone. Everyone I show it to is very impressed. Worryingly, not all of them seem to believe that I was stationary at traffic lights at the time and had a faulty speedo

[V8 Animal]

Booked it in at peter smith for tommorow i'll keep you informed.
Could'nt carry on like this causing me too much worry i already have 6 points.
Animal

[v8 animal]

Took my car to peter smith and they fitted a new sensor.Same problem exists £350 lighter and more pi++ed of than i was before.
So it must be the speedo i have'nt a clue how to get it out or where to send it.
Can anyone advise me??

[sparkythecat]

v8 animal said:

Took my car to peter smith and they fitted a new sensor.Same problem exists £350 lighter and more pi++ed of than i was before.
So it must be the speedo i have'nt a clue how to get it out or where to send it.
Can anyone advise me??

I don't know who Peter Smith is, but ask him what gap he set the sensor to. It should be around 6 thou'
The sensor costs around £80 and the job takes no more than an hour (including break for fag and a brew). Why on earth have you got a bill for £350? Have they filled the ashtray with saffron, myrrh or crack cocaine ?

[v8 animal]

sparkythecat said:

v8 animal said:

Took my car to peter smith and they fitted a new sensor.Same problem exists £350 lighter and more pi++ed of than i was before.
So it must be the speedo i have'nt a clue how to get it out or where to send it.
Can anyone advise me??

I don't know who Peter Smith is, but ask him what gap he set the sensor to. It should be around 6 thou'
The sensor costs around £80 and the job takes no more than an hour (including break for fag and a brew). Why on earth have you got a bill for £350? Have they filled the ashtray with saffron, myrrh or crack cocaine ?

They say they have gapped it right did'nt really want to ask the question they are dealers and should know what they are doing.
3 hours labour plus part plus vat.
Animal