I think I have traced the problem of the speedo cutting out intermittedly in my 2002 to the sender that screws into the side of the transmission and two wires inside that come adrift through poor soldering.
There was a fix on Miata.net that involves removing it and resoldering the broken connection and repacking it in goo or silicon.
Still haven't attempted it but starting to think maybe one from a wreck might be an easier option?
Anyone know where to find one in Qld. and how much it would cost and if the replacement job is difficult for a non mechanical guy?
Speedo cutting out sometimes....
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Speedo cutting out sometimes....
Silver Nomad
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Re: Speedo cutting out sometimes....
Hi Silvi,
Check out your old thread, remove the sender and take it to your local ham radio bloke or computer geek along with a copy of the test instructions here, the viewtopic.php?f=29&t=42521#p545781
If it is only loose joints they will fix it in a jiffy.
Greg.
Check out your old thread, remove the sender and take it to your local ham radio bloke or computer geek along with a copy of the test instructions here, the viewtopic.php?f=29&t=42521#p545781
If it is only loose joints they will fix it in a jiffy.
Greg.
When you turn your car on, does it return the favour?
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Re: Speedo cutting out sometimes....
Thanks Greg I'm thinking I would love to hand someone some dollars in Sunshine Coast or Bris. to do it (within reason of course) as I'm in a unit with limited garage space to operate.
While the manual instructions say to drain transmission oil , seems to be possible to just jack up the rear and remove the sensor without doing this?.
While the manual instructions say to drain transmission oil , seems to be possible to just jack up the rear and remove the sensor without doing this?.
Silver Nomad
2002 NB8C
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Re: Speedo cutting out sometimes....
I did this a few months ago.
You can jack up the rear really high and not spill a drop of transmission oil.
The sensor is one bolt and a plug the other end.
The hardest part is getting past all the bracing but I don't think you'll have that on an 2002 model.
See my garage thread for more info
You can jack up the rear really high and not spill a drop of transmission oil.
The sensor is one bolt and a plug the other end.
The hardest part is getting past all the bracing but I don't think you'll have that on an 2002 model.
See my garage thread for more info
MeepMeep
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Re: Speedo cutting out sometimes....
Thanks RR, Had a look and it looks approachable though I don't have a soldering iron, I will have a go. One bonus from looking up your excellent garage notes - btw great work, excellent photos - was to find out there is a code for the speedo sensor failure. I had a warning come up one day far from home but before I could have it read it it went off again. Car has been going perfectly ever since . I now suspect it was that warning about the sensor, which continues to fail at times.
Re. the stiff gearbox, when I bought my 2002 it was impossible not to crunch changes when cold , particularly 1-2 changes.
After some research I located some Red Line MT90 oil in Brisbane which was highly recommended and dropped it in. Dramatic change, much smoother changes and no crunching. Seems the viscosity of the oil is critical in helping the synchro match gear speeds and this is one of the transmission oils that work.
Cheers
Re. the stiff gearbox, when I bought my 2002 it was impossible not to crunch changes when cold , particularly 1-2 changes.
After some research I located some Red Line MT90 oil in Brisbane which was highly recommended and dropped it in. Dramatic change, much smoother changes and no crunching. Seems the viscosity of the oil is critical in helping the synchro match gear speeds and this is one of the transmission oils that work.

Cheers
Silver Nomad
2002 NB8C
2002 NB8C
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Re: Speedo cutting out sometimes....
Silvia wrote:...was to find out there is a code for the speedo sensor failure. I had a warning come up one day far from home but before I could have it read it it went off again.
If the battery hasn't been disconnected the fault code gets stored in the ECU, & an OBDII reader could confirm, but sounds like a PO500: http://www.obd-codes.com/p0500
Post # 5 also details how to fix from raising vehicle to testing finished product: http://forum.miata.net/vb/showthread.php?t=469684
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Re: Speedo cutting out sometimes....
I'm into the fix first chance I get. Thanks all.
Good to know there's a website where you can check codes. Was quoted $100 locally to read and find code meaning.
Good to know there's a website where you can check codes. Was quoted $100 locally to read and find code meaning.
Silver Nomad
2002 NB8C
2002 NB8C
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Re: Speedo cutting out sometimes....
Speedo fix done , twice in fact as a local mate has a 2004 that started doing the same thing. Took about an hour each using the Garage instructions here and from miata.net .Thanks all. Both work fine now and only cost was a $8 tube of Permatex RTV silicon.
Suggest blocks under front wheels as space underneath is tight for crawling under otherwise. With rear jacked up no trans. oil was lost. Good one

I'm sure now the CEL warning I got earlier was from this speedo fault
No use buying a replacement - probably has same problem.
Suggest blocks under front wheels as space underneath is tight for crawling under otherwise. With rear jacked up no trans. oil was lost. Good one


I'm sure now the CEL warning I got earlier was from this speedo fault
No use buying a replacement - probably has same problem.
Silver Nomad
2002 NB8C
2002 NB8C
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