C3 Speedometer Error
Thread Starter
Burning Brakes
Joined: Apr 2013
Posts: 1,194
Likes: 109
From: Las Vegas NV
C3 Speedometer Error
My speedometer is off pretty bad. Around 70-80 mph it starts to read accurate, but at lower speeds its almost worthless.
I noticed that I have to be going about 15 mph before the needle even starts to move.
Doesn't seem to be a problem with the wrong gear, seems to be more like a worn out part. Maybe the cable is bad or the speedometer itself is going out.
This car sat for 10 years before I bought it a few months ago.
Any advice? My tach is all wonky and jumps around too, but I think that can be cured with a new tach filter.
My temp gauge and possibly fuel gauge are toast, I'm planning on putting new gauges in the center (and add some A/F and vacuum gauges) but would like to continue to use my original tach and speedo.
I noticed that I have to be going about 15 mph before the needle even starts to move.
Doesn't seem to be a problem with the wrong gear, seems to be more like a worn out part. Maybe the cable is bad or the speedometer itself is going out.
This car sat for 10 years before I bought it a few months ago.
Any advice? My tach is all wonky and jumps around too, but I think that can be cured with a new tach filter.
My temp gauge and possibly fuel gauge are toast, I'm planning on putting new gauges in the center (and add some A/F and vacuum gauges) but would like to continue to use my original tach and speedo.
Thread Starter
Burning Brakes
Joined: Apr 2013
Posts: 1,194
Likes: 109
From: Las Vegas NV
Thanks. That's not what I wanted to hear, but I'll take it.
What makes you guys so sure it's the gauge simply based off what I said? The more I think about how a gauge works, the more it makes sense that the gauge is the problem. I wonder if I can take it apart and clean and maybe even oil it and get it working again.
What makes you guys so sure it's the gauge simply based off what I said? The more I think about how a gauge works, the more it makes sense that the gauge is the problem. I wonder if I can take it apart and clean and maybe even oil it and get it working again.
Thread Starter
Burning Brakes
Joined: Apr 2013
Posts: 1,194
Likes: 109
From: Las Vegas NV
One challenge I have is that I'm restricted to 5,000 miles/yr with the tags I have otherwise I have to pass emissions. If I change my speedometer, I'll need the new one to match the mileage. I suppose I could get a new autometer unit or something similar and try to manually roll the mileage up.
I suppose I could try to get through the DMV and get them to recognize the speedometer change, but if they screw something up I'll be required to pass emissions and that will be a huge problem.
I'll probably just leave it for a while
I suppose I could try to get through the DMV and get them to recognize the speedometer change, but if they screw something up I'll be required to pass emissions and that will be a huge problem.
I'll probably just leave it for a while
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Melting Slicks
Joined: Apr 2001
Posts: 2,030
Likes: 363
From: Lubbock Texas
I ended up replacing all my gauges with Auto Meter including the speedo and tach.
The Auto Meter speedo can be calibrated by the owner anytime a change is made to gearing, tire size, etc.
I bought the Auto Meter gauges from Summit Racing. I contacted Auto Meter and asked if there was an easy way I could set the odometer to match my old one. They said there was not a way for the end user to change the odometer but they could do it for me. So, I shipped the new speedo back to Auto Meter and a week later it showed up with the correct reading on the odometer. Hats off to Auto Meter.
DC
Thread Starter
Burning Brakes
Joined: Apr 2013
Posts: 1,194
Likes: 109
From: Las Vegas NV
DC3, thanks for the info! That's good to know.
I imagined I'd have to rig up something and power up the speedo and fool it into thinking it is in a car moving at 200mph and leave it running for a while
Your method is better
I imagined I'd have to rig up something and power up the speedo and fool it into thinking it is in a car moving at 200mph and leave it running for a while
Your method is better
Racer
Joined: Oct 2011
Posts: 318
Likes: 3
From: NP Nebraska
I had issues with the speedo in my '73. I sent it off twice to be repaired and calibrated but the best they could do was get it accurate at one speed which turned out to around 60 MPH. It was off too much at all other speeds.
I ended up replacing all my gauges with Auto Meter including the speedo and tach.
The Auto Meter speedo can be calibrated by the owner anytime a change is made to gearing, tire size, etc.
I bought the Auto Meter gauges from Summit Racing. I contacted Auto Meter and asked if there was an easy way I could set the odometer to match my old one. They said there was not a way for the end user to change the odometer but they could do it for me. So, I shipped the new speedo back to Auto Meter and a week later it showed up with the correct reading on the odometer. Hats off to Auto Meter.
DC
I ended up replacing all my gauges with Auto Meter including the speedo and tach.
The Auto Meter speedo can be calibrated by the owner anytime a change is made to gearing, tire size, etc.
I bought the Auto Meter gauges from Summit Racing. I contacted Auto Meter and asked if there was an easy way I could set the odometer to match my old one. They said there was not a way for the end user to change the odometer but they could do it for me. So, I shipped the new speedo back to Auto Meter and a week later it showed up with the correct reading on the odometer. Hats off to Auto Meter.
DC
Pro
Joined: Aug 2010
Posts: 632
Likes: 38
From: Roseville CA
I installed a GPS HUD. I never have to look down anymore and it matches the speed on my nav system.
ARTICLE ON INSTALL
ARTICLE ON INSTALL
Thread Starter
Burning Brakes
Joined: Apr 2013
Posts: 1,194
Likes: 109
From: Las Vegas NV
That's interesting!
I have a speedometer app in my phone and a suction mount, so i have basically the same thing. I don't always put it up, but it was useful for matching speed to rpm. Now I know 3,000 rpm in 4th is approx. 65 mph for example.
I think I've sold myself on the electric programmable speedometer option. I like that it can be calibrated so easily. I have brand new 225/60/15 all around (previous owner installed them) and I will put on a different size later...probably 255/60/15 or a different wheel size.
I just have to finish up my research so I understand how to install it with the drivetrain I have now.
I have a speedometer app in my phone and a suction mount, so i have basically the same thing. I don't always put it up, but it was useful for matching speed to rpm. Now I know 3,000 rpm in 4th is approx. 65 mph for example.
I think I've sold myself on the electric programmable speedometer option. I like that it can be calibrated so easily. I have brand new 225/60/15 all around (previous owner installed them) and I will put on a different size later...probably 255/60/15 or a different wheel size.
I just have to finish up my research so I understand how to install it with the drivetrain I have now.
Melting Slicks
Joined: Apr 2001
Posts: 2,030
Likes: 363
From: Lubbock Texas
I think I've sold myself on the electric programmable speedometer option. I like that it can be calibrated so easily. I have brand new 225/60/15 all around (previous owner installed them) and I will put on a different size later...probably 255/60/15 or a different wheel size.
I just have to finish up my research so I understand how to install it with the drivetrain I have now.
I just have to finish up my research so I understand how to install it with the drivetrain I have now.
I used this AutoMeter Hall Effect sender (#5291) to get the signal from the transmission to the new speedo: http://www.autometer.com/cat_accesso...l.aspx?vid=114
DC