Fuel / boost
- Thread starter gtsteve
- Start date
Just had the same issue on my low mileage car.
I ended up purchasing a brand new fuel gauge, that is the quickest fix.
fjpikul
GT Owner
Should be a gauge problem. You can order a new gauge directly from AutoMeter, but they seem to make them in batches. There is a lot of info here on the Forum. Search can be your friend. Pulling the dash is a major pain to replace.
twobjshelbys
GT Owner
Please, please, check your battery (and potentially replace it) before swapping gauges. In many instances that is the fix and it's cheaper and less time consuming of a fix and you'll probably need one soon anyway. Even if you don't replace it just cable in a known good battery from another car can tell you if the battery is the cause. (Do NOT jumper!)
extrap
GT Owner
Is this what you mean by "cable in a new battery"? Remove the car's negative cable and connect it to a known good battery's negative terminal, then jumper from the known good battery's positive terminal to the existing battery's positive terminal. This will remove the existing battery from the circuit and cause power to be drawn from only the known good battery.
Testing this way at least you don't have to lift the existing battery out of the car, and set the known good one in ... until if/when you determine the existing one is bad.
Respectfully, I emphatically disagree with Tony regarding diagnosing gauge issues - and further I would not recommend the procedure described above. I would have no qualms with jump-starting the GT - as long as ordinary care is taken to connect the cables properly.
Regarding gauge "issues". There are two potential problems - and as far as any data would suggest there is NO connection between the two:
Issue 1: Seemingly at random, one or more gauges will not function during an entire run sequence. Turning the car off and re-starting will often cause this problem to remedy itself. Response: This is a known-problem and is typically caused by a battery that exhibits a low voltage - traditionally a battery at or nearing end-of-life. The problem occurs because at each start sequence the gauges individually "check-in" via the canbus network. Low battery voltage impedes the check-in process and occasionally one or more gauges are "missed". When missed, the gauge control module will wait until the next start sequence to try again.
Issue 2: A deceased gauge. In this scenario, a gauge simply does not work. To differentiate from above, if the same gauge does not function across multiple start cycles - and particularly after a warm start (where battery voltage should be near-normal), then the gauge itself should be replaced. As stated previously, Issue 1 has not been shown to cause or exacerbate issue 2.
It should be fairly straightforward to diagnose between issue 1 and issue 2 and take appropriate steps. In 99.9% of the cases a new, fresh date code battery will resolve issue 1 and issue 2 can be resolved by replacing the gauge.
No jumping, wiring-in, standing on left foot and twirling counter-clockwise theatrics are needed. In contrast, it should take just a few minutes and common sense to determine the best course of action.
Regarding gauge "issues". There are two potential problems - and as far as any data would suggest there is NO connection between the two:
Issue 1: Seemingly at random, one or more gauges will not function during an entire run sequence. Turning the car off and re-starting will often cause this problem to remedy itself. Response: This is a known-problem and is typically caused by a battery that exhibits a low voltage - traditionally a battery at or nearing end-of-life. The problem occurs because at each start sequence the gauges individually "check-in" via the canbus network. Low battery voltage impedes the check-in process and occasionally one or more gauges are "missed". When missed, the gauge control module will wait until the next start sequence to try again.
Issue 2: A deceased gauge. In this scenario, a gauge simply does not work. To differentiate from above, if the same gauge does not function across multiple start cycles - and particularly after a warm start (where battery voltage should be near-normal), then the gauge itself should be replaced. As stated previously, Issue 1 has not been shown to cause or exacerbate issue 2.
It should be fairly straightforward to diagnose between issue 1 and issue 2 and take appropriate steps. In 99.9% of the cases a new, fresh date code battery will resolve issue 1 and issue 2 can be resolved by replacing the gauge.
No jumping, wiring-in, standing on left foot and twirling counter-clockwise theatrics are needed. In contrast, it should take just a few minutes and common sense to determine the best course of action.
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extrap
GT Owner
Would like to learn why you would not recommend my temp wiring plan? Just not needed? Or is something bad about it? Tks
Pure waste of time. The gauge issue is pretty straightforward. For completeness; perhaps we should discuss a 3rd symptom;
Symptom 1: One or more gauges do not work for a start cycle duration. But on another start cycle they WILL work.
Remedy: Replace or charge battery
Symptom 2: One or more gauges are dead and have remained dead across multiple start cycles. Needle never moves.
Remedy: Gauge is bad. Replace gauge.
Symptom 3: Gauge works but is erratic. Two possibilities here: Try to detect if erratic behavior is due to a "sticky" needle. This is most common with speedo and tach and often precedes total failure. A sticky needle will be "notchy"... pausing and then jumping. I would try to live with a sticky needle... but ultimately the gauge will need to be replaced. Again, sticky needles are most common in speedo and tach.
Gauge can also be erratic showing incorrect values but doesn't really appear to be sticky. Historically, the Oil Pressure gauge and (less common) the water temp gauge. An erratic gauge can be caused by a faulty sending unit. The Oil Pressure and water temp sending units are both not GT-specific, relatively low cost (~$30), and relatively accessible. If you have an erratic Oil Pressure or Water temp gauge, I would recommend replacing the corresponding sending unit as one of first steps of diagnosis.
twobjshelbys
GT Owner
Yes, disconnect the cables from the old battery and connect to the new, You might have to remove the old battery to get the cables connected to the new one since they are not overly long.
I did mine with one of the "jumper batteries" which is a standalone unit, not a vehicle-to-vehicle connection. Not everyone has one of those available. The units cables are extension cables but it's not trying to saddle on the existing battery which may be faulty.
I don't care if you try it or not. Worked for me to confirm the battery was the issue.
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If you need new gauges then either contact us here in the UK or talk to André at Autohaus Hagemeier in Halle Westfalen. We buy in direct from the supplier and have supplied several to Hagemeier in the past.
Joehand1
Tungsten GT Owner
