Speedometer and Tach rebuild


Specracer

GT Owner
Mark IV Lifetime
Nov 28, 2005
7,146
MA
But only the speedo and tach go to Rich. Get the small gauges directly from Autometer. If you have bad small gauges and have the panel out it is suggested to replace them all - the cost isn't that much.

If you have a bad big gauge, I wonder if it is worthwhile to preemptively have the other one done too? I had my gauges out to replace one too. It wasn't too intimidating - just take your time - but if you have a shop do it it's all labor and the price to get both gauges bullet-proofed is maybe worth the extra cost while it's all apart. Rich, what do you think??
I know.
 

Stef

GT Owner
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Le Mans 2010 Supporter
Apr 5, 2009
1,107
Southern California
I am sure Rich would do it for free if he got the new GT Garage plastered for free.

🤣
Sure, why not.
Plaster and Drywall his shop for life long mechanical privileges, I'm in.
We should all go on the barter system. with surgeons, attorneys, pilots, etc etc on here some great deals could be had.
 

Stef

GT Owner
Mark IV Lifetime
Le Mans 2010 Supporter
Apr 5, 2009
1,107
Southern California
I let my local Ford dealer install a new fuel gauge a few years back. The technician scratched the hell out of the leather dash. So off my GT went to Rich’s to get the dash reskinned and while it was there I had him replace all the small gauges with new revised Autometer OEMs. All of the small gauges are still working perfectly. I’m probably about to jinx myself but I’m still running the original Speedometer and Tach. Knock on wood.

Or my head (same thing at times)
for letting myself start the car with an almost dead battery.
 

Rick Mustang

GT Owner
Mar 29, 2016
106
Central Texas
I’m doing both when only my tach is out. Doing all remaining small gauges too. I want to do this job only one time. Thanks for your help Rich!
 

ttn27

GT Owner
Sep 7, 2014
38
Can anybody provide a link of where to get the Autometer small gauges?

My speedometer gauge was working intermittently. It stays at zero than start working after a couple of drives. When it does work, the needle jumps from zero to 10 mph and increases smoothly with increase in speed and then a small jump from 10 to zero when I come to a stop. Finally it stops working. Tach and other gauges are fine. I have to check the battery, but if the battery is good, how likely is it the speedometer sensor is the cause?
 
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Special K

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Aug 23, 2016
1,781
Franklinton, LA
Can anybody provide a link of where to get the Autometer small gauges?

My speedometer gauge was working intermittently. It stays at zero than start working after a couple of drives. When it does work, the needle jumps from zero to 10 mph and increases smoothly with increase in speed and then a small jump from 10 to zero when I come to a stop. Finally it stops working. Tach and other gauges are fine. I have to check the battery, but if the battery is good, how likely is it the speedometer sensor is the cause?
I would try a new speed sensor first, that sounds like the culprit to me.
 
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twobjshelbys

GT Owner
Jul 26, 2010
6,178
Las Vegas, NV
Can anybody provide a link of where to get the Autometer small gauges?

My speedometer gauge was working intermittently. It stays at zero than start working after a couple of drives. When it does work, the needle jumps from zero to 10 mph and increases smoothly with increase in speed and then a small jump from 10 to zero when I come to a stop. Finally it stops working. Tach and other gauges are fine. I have to check the battery, but if the battery is good, how likely is it the speedometer sensor is the cause?
How old is the battery? I'd start there first.
 

fjpikul

GT Owner
Mark IV Lifetime
Le Mans 2010 Supporter
Jan 4, 2006
11,673
Belleville, IL
Just Google Autometer in northern Illinois. Call them and explain you want FordGT guages. There is one salesperson that handles it. They batch build them so there will be some waiting. There are several old threads here covering the whole issue.
 
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ttn27

GT Owner
Sep 7, 2014
38
How old is the battery? I'd start there first.
Last battery was Ford OEM battery, replaced in April 2016, though it is always maintained on a Deltran trickle charger.
 

twobjshelbys

GT Owner
Jul 26, 2010
6,178
Las Vegas, NV
It's time for a new one. I got 7 yrs out of mine with the charger on it too.

Ford thinks very highly of their battery. It's just an optimal that you can get from autozone or O'Reillys. If you love the label they are available
 

nota4re

GT Owner
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Le Mans 2010 Supporter
Feb 15, 2006
4,279
A "sticky" gauge needle is the first sign of a failing tach/speedo. Highly unlikely that it is either the battery or the sending unit based on this description.
 

ttn27

GT Owner
Sep 7, 2014
38
A "sticky" gauge needle is the first sign of a failing tach/speedo. Highly unlikely that it is either the battery or the sending unit based on this description.
Is there anyway to test to see if it is a bad speedo sensor before actually removing the instrument cluster and sending the speedo in to Rich for a rebuilt?
 

twobjshelbys

GT Owner
Jul 26, 2010
6,178
Las Vegas, NV
W
Is there anyway to test to see if it is a bad speedo sensor before actually removing the instrument cluster and sending the speedo in to Rich for a rebuilt?
Well, you still can't discount the battery. At its age you're going to need one soon anyway so replacing it would be both a preemptive move and a potential fix.

If you don't want to put out for a new battery now (but you will soon anyway) just temporarily connect up another battery. It doesn't need to fit perfectly, just stable tied down with some straps so it doesn't move around. Leave the frunk liner out and take it for a test drive to confirm...
 

nota4re

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Feb 15, 2006
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Well, you still can't discount the battery.
Well, yes you can. A low battery voltage will inhibit the initial handshake of the gauge control module and each gauge. One or more gauges may fail to initiate at start-up and those gauge (if any) will be inoperative throughout that entire drive cycle. They only try to do the the handshake at start-up and if it fails, that's it for that drive cycle. A funky/sticky speedometer that exhibits that behavior through multiple drive cycles will eliminate the battery as a cause.
 
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ttn27

GT Owner
Sep 7, 2014
38
W

Well, you still can't discount the battery. At its age you're going to need one soon anyway so replacing it would be both a preemptive move and a potential fix.

If you don't want to put out for a new battery now (but you will soon anyway) just temporarily connect up another battery. It doesn't need to fit perfectly, just stable tied down with some straps so it doesn't move around. Leave the frunk liner out and take it for a test drive
The battery tester confirmed that the battery is still good. I would think that a marginal battery would have caused intermittent issues with the other gauges also. By the way, Ford have upgraded their OEM battery from a Motorcraft to an Optima battery which is almost 3x the cost of the Motorcraft.
 
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fjpikul

GT Owner
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Jan 4, 2006
11,673
Belleville, IL
They never used a Motorcraft to my knowledge. The originals were special issue "black" Optimas. You can buy from Ford, get the GT sticker with it, or buy a regular (read same) for a lot less and a lot quicker at OReilly or AutoZone.
 

ttn27

GT Owner
Sep 7, 2014
38
Well, yes you can. A low battery voltage will inhibit the initial handshake of the gauge control module and each gauge. One or more gauges may fail to initiate at start-up and those gauge (if any) will be inoperative throughout that entire drive cycle. They only try to do the the handshake at start-up and if it fails, that's it for that drive cycle. A funky/sticky speedometer that exhibits that behavior through multiple drive cycles will eliminate the battery as a cause.
The battery tester indicated that the battery is still good, not marginal.
It is interesting to note that after the sticky Speedo stopped working after my last drive, the check engine light came on with the next drive cycle. What is also interesting is that the engine temperature gauge, which did not work at the beginning of the drive and then jumped immediately to operating temp at around 180-190, but only after I parked my car with engine in idle, i.e. becoming sticky?
My question is that a failure of any gauge, such as Speedo or engine temp, etc…, will that trigger a check engine light? or does failure of a Speedo sensor also trigger the check engine light?
 

PeteK

GT Owner
Mark II Lifetime
Apr 18, 2014
2,460
Kalama, Free part of WA State
With multiple coincident problems, it sounds to me like a possible electrical problem which is causing the gauge problems and triggering the CEL. This suggests a bad ground connection. Start with the ground cable at the battery. Remove and carefully clean, then grease, then reinstall the cable to the battery, and where it bolts to the chassis. Look for any corrosion at any electrical connections you can see and reach.
 
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GT@50

GT Owner
Mark II Lifetime
Dec 14, 2019
936
Issaquah
Check engine or check gauges light? They're different. Check gauges means to look at gauges, something is up. Mine comes on for low fuel. Check engine sets with a code so check codes. I just finished getting a 3800 miler road ready. A ground on drivers side of engine, on frame, down low was loose. Just something to check everybody.
 
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nota4re

GT Owner
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Le Mans 2010 Supporter
Feb 15, 2006
4,279
It may not be a check engine light? The check engine light is a yellow light with an engine icon. The "Check Gauges" light is red and has been confused with the check engine light frequently. Do you have a yellow check engine light? In answer to you question, a gauge problem will not trigger a check engine light.