I have only 2 reliable gauges my tach and my volt gauge.
1.Speedometer:It does read speed but it bounces and reads roughly 10-15 less then what I am going. I already swapped the head unit and same problem so I don't know where to go with this next.
2.Temp. Gauge: This gauge is completely dead and I have a sending unit on order for it.
3.Oil pressure Gauge: Readings are low and erratic will drop to 0 out of no where and will drift between the m, a, l. I haven't noticed any performance problems or strange noises, I am hoping it is the sender so I ordered one of them as well.
4.Gas Gauge: This gauge used to read full all the time until I swapped it out with a new gauge and now the needle has rotated down behind the gauge. When I was driving tonight my low fuel light started to flicker and now it is on steady, the problem is I have a full tank of gas!
If anyone thinks they may be able to help feel free to post your opinions
__________________
1987 Mustang GT Only mods are no cats and 40's
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Bump. I really need some help on this one I am going to pick at the gauges today and see what I can find. I someone has had something similar happen with there gauges which should be quite possible since we all drive fords.
First things first... Have the gauges been replaced at any time? like for a 140mph gauge upgrade or perhaps stock gauges broke.
2. does it still have stock dash, engine, & body harness?
If either of those are possible your gauges could be pinned wrong which is a simple fix.
If you bought the car & all were a problem then it's a possibility that the sending units are bad. It's a little awkward but a possibility. Seeing as how quite a few of the gauges have a problem I'd say your problem is more than likely in wiring. More than likely a bad ground wire on the gauges. Could also be the power wire. You can look at the back of the gauges & trace where the wires go to look for a problem. All of the gauges are setup pretty well the same, either a power & ground setup... or a power, signal, ground setup. Signal would go to the sensor.
Diagnosing a problem there is simple. while the gauges are out a little bit (but still connected) with the car running you run a 12v source to the positive, if it changes that's the problem, bad power source, if not try jumping a wire from the gauge ground to a good ground source (like a bolt going into the frame). If that changes nothing run a wire directly from the sending unit to the signal for the gauge. If nothing changes then the sending unit or the gauge is faulty.
May take a couple hours, but it comes down to if you want to spend money & replace blindly or find the problem then spend money.
As for changing the fuel sending unit it's fairly easy. Unbolt the filler neck. then two bolts hold the fuel tank straps on, undo those. Then you should be able to drop the tank (it's best to do this with little fuel in the tank, they can get heavy).
The fuel sending unit is the one not on the hump of the tank. Take a screwdriver & hammer, then lightly tap the locking ring to turn it. Then you just take the unit out. Installation is reverse. Make sure the o-ring is still good where the sending unit sits on the tank before reinstalling.
let us know how it goes & if you need further help.
__________________
If you have to ask what it takes to get to 500 HP, you don't have what it takes to get there.
'89 Mustang GT
'86 Mustang vert
'84 Mustang notch turbocharged
'96 Mustan
First things first... Have the gauges been replaced at any time? like for a 140mph gauge upgrade or perhaps stock gauges broke.
2. does it still have stock dash, engine, & body harness?
If either of those are possible your gauges could be pinned wrong which is a simple fix.
If you bought the car & all were a problem then it's a possibility that the sending units are bad. It's a little awkward but a possibility. Seeing as how quite a few of the gauges have a problem I'd say your problem is more than likely in wiring. More than likely a bad ground wire on the gauges. Could also be the power wire. You can look at the back of the gauges & trace where the wires go to look for a problem. All of the gauges are setup pretty well the same, either a power & ground setup... or a power, signal, ground setup. Signal would go to the sensor.
Diagnosing a problem there is simple. while the gauges are out a little bit (but still connected) with the car running you run a 12v source to the positive, if it changes that's the problem, bad power source, if not try jumping a wire from the gauge ground to a good ground source (like a bolt going into the frame). If that changes nothing run a wire directly from the sending unit to the signal for the gauge. If nothing changes then the sending unit or the gauge is faulty.
May take a couple hours, but it comes down to if you want to spend money & replace blindly or find the problem then spend money.
As for changing the fuel sending unit it's fairly easy. Unbolt the filler neck. then two bolts hold the fuel tank straps on, undo those. Then you should be able to drop the tank (it's best to do this with little fuel in the tank, they can get heavy).
The fuel sending unit is the one not on the hump of the tank. Take a screwdriver & hammer, then lightly tap the locking ring to turn it. Then you just take the unit out. Installation is reverse. Make sure the o-ring is still good where the sending unit sits on the tank before reinstalling.
let us know how it goes & if you need further help.
Thanks a million for the response. I only have 2 completely lifeless gauges that is the temp and fuel level. When I bought it the fuel level was at the top and someone on here was able to tell me that when the wiring was unplugged at the sender the gauge would go straight to the top. I think I may have put the needle on wrong or something when I had them out.
The temp gauge was like my fuel gauge is now gone down behind so I put a new one in and put the needle on 0 and installed it, it has not moved. I have a temp switch/sender on my coffee table I am going to put in when I get a chance. I am hoping that should fix that one.
I don't think the temp could be a ground off since it is running on the same harness as the oil pressure. My car is a original 8cyl and still SD so I am hoping I have the original harness but car fax says I don't have the original cluster though.
I'd say concentrate one one at a time. In this case the temp. Did you ever get the temp sending unit? If the wiring is good to it then I'd say it's going to be faulty or you're very low on coolant, check the rad when it's cool (also turn the heat on when engine has been running a while & see if it blows hot to check to see if it's all the way full)
Other than that it's going to be in the wiring or sending unit. You said you replaced the gauge?
As always I'd check the wiring first so you don't have to spend $.
I personally don't trust the stock ones anyway first upgrades i always recommend is aftermarket mechanical oil psi & water temp gauges.
__________________
If you have to ask what it takes to get to 500 HP, you don't have what it takes to get there.
'89 Mustang GT
'86 Mustang vert
'84 Mustang notch turbocharged
'96 Mustan
Help me fix my gauges.
