Speedometer and Tach rebuild
- Thread starter thegtguy
- Start date
Stef
GT Owner
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
Or my head (same thing at times)
for letting myself start the car with an almost dead battery.
Rick Mustang
GT Owner
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!
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?
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?
Special K
GT Owner
I would try a new speed sensor first, that sounds like the culprit to me.
twobjshelbys
GT Owner
fjpikul
GT Owner
Last battery was Ford OEM battery, replaced in April 2016, though it is always maintained on a Deltran trickle charger.
twobjshelbys
GT Owner
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
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
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
W
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...
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...
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 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
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.
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
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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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.
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.