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nikp
1st June 2005, 02:20 PM
Ok, I seem to have some sort of speedo problem at the moment. It's difficult to demonstrate exactly what is wrong, because it's so strange. Anyway, most of the time it's definately wrong! It seems that a lot of the time it reads in KPH, sometimes it flicks back to MPH, and sometimes, we suspect it reads somewhere in between.

Also, the rev counter may be off too. Not sure. It's only a suspicion that the rev counter is wrong - I have certainly see it move when the engine revs are not changing! (For example, when cruising down the motorway I can see the revs change even though I am at constant speed). I'm not sure whether the revs read right when the speedo reads wrong, or whether the revs read wrong only when the speedo reads wrong, or whether they're completely independant of each other!

The idle seems to show 1500 even though it seems to be nice and slow and regular like the approx 750 it should be.

I am wondering whether it's actually read 8/5 times that of what the revs should be - just like an inverse conversion of MPH to KPH. I am pretty confident that it has a speedo converter wired into the electronics behind the dash, as i have seen something wired into the loom that I wouldn't expect to see there. I have also seen some suspect wiring in the loom in another place, which I have corrected, so I was wondering whether the speedo converter could just be wired in with rubbish soldering.

Sorry about the long post - but if anyone can offer advice or help, it would be most aprreciated! It's doing my nut in! :)

nikp
1st June 2005, 07:06 PM
Could it be a Goosed instrument cluster? It seems ok, but so does the soldering for all the connections of the converter. Or could the converter be duff?

nikp
1st June 2005, 08:33 PM
Ok, I'm getting desperate and depressed now! :(

I figured if i just remove the converter then the speedo will just read a nice reliable KPH and restore anything that was a bit iffy.

How wrong I was!

Now I have NO speedo, and the revs are still wierd. It seems to show the correct idle speed, but I went well past 7.5k revs - I went to 8.5k displayed revs - which I'm sure I wasn't really doing that sort of engine speed....so I am well and truly confused! Any help....Please!

Anyone. It's really getting me down.

Donato
2nd June 2005, 07:37 AM
Best thing to do would be borrow an instrument cluster and change over to see if it fixes the problem, my speedo is knackered so i just bought a road angel! :)

nikp
2nd June 2005, 08:46 AM
That would be a good idea - shame i don't know anyone else close to me willing to lend me an instrument cluster! :(

Pooey!

Donato
2nd June 2005, 08:50 AM
Find out the price for them second hand, you will probably find they wont be that much...

Try tim at rx motors or andrew at jimmys.

Cheers

Donato

nikp
2nd June 2005, 09:23 AM
Ok, good plan. cheers.

Donato
2nd June 2005, 09:29 AM
No probs, if it works please post up so others will know what to do in the event of it happening to them...

Cheers

Donato

nikp
2nd June 2005, 10:11 AM
Ok dokes. However, I have a funny feeling it won't, but i'll try it anyway!

nikp
2nd June 2005, 01:03 PM
I phoned RX motors at lunchtime - I was told that it won't be the instrument cluster, but in fact the converter. So I'm gonna replace that with one that they have.

Donato
2nd June 2005, 01:15 PM
I didnt think the speed convertor chip would effect the rev counter... you live and learn! :)

nikp
2nd June 2005, 01:30 PM
Admittedly i didn't mention that - I will when i go down there on saturday. Maybe it is the instrument cluster after all....basically, I'm very confused! :confused: :confused: :confused:

Donato
2nd June 2005, 01:33 PM
it could be both :(

nikp
2nd June 2005, 01:55 PM
Well, i suppose i can have a chat on saturday and get some advice from RX motors.

At least i know they have both parts in stock!

nikp
13th June 2005, 12:16 PM
Right, as Donato suggested, i am posting the results of my findings:

Firstly, don't think there's anything wrong with the rev counter - a slipping clutch didn't help me diagnose the problem!

The problem was a sticking speedo. I went to RX motors who supplied me with a replacement speedo (A UK one, so it's already converted, reads in mph and kph, and the trip computer is in miles - Bonus!) and i fitted it, and now it reads pucker like! So, it was as Donato suggested in the first place - thanks for the help.

Donato
13th June 2005, 12:20 PM
No probs, Glad you have got to the bottom of it. shame about the clutch...

Cheers

Donato

nikp
13th June 2005, 12:23 PM
Just as I got the engine problems sorted too! Gonna try and replace the clutch myself! <Gulp!>

Donato
13th June 2005, 12:28 PM
There should be lots of info on changing a clutch on the two links below, remember they are American so drivers side is reverse of ours...

http://www.rx7.org/Robinette/

http://www.scuderiaciriani.com/rx7/index.html

Cheers

Donato