[uglyryder]

i havent had the mustang long i just replaced the sending units for the temp and oil gauge, the oil gauge seems to be working like its supposed to. but i went on a 10 min drive and the temp gauge only went to just before the N, but when i got back home and turned the car off the needle went way right about a half inch further past the H. any ideas of how i can fix this?

[toyman]

Originally Posted by uglyryder

i havent had the mustang long i just replaced the sending units for the temp and oil gauge, the oil gauge seems to be working like its supposed to. but i went on a 10 min drive and the temp gauge only went to just before the N, but when i got back home and turned the car off the needle went way right about a half inch further past the H. any ideas of how i can fix this?

You didn't say why or what the gauges were doing/not doing before they were changed. I'll go out on a limb and guess the problem is an engine grounding issue. Battery to engine and engine to chassis.

[302Feen]

Originally Posted by uglyryder

i havent had the mustang long i just replaced the sending units for the temp and oil gauge, the oil gauge seems to be working like its supposed to. but i went on a 10 min drive and the temp gauge only went to just before the N, but when i got back home and turned the car off the needle went way right about a half inch further past the H. any ideas of how i can fix this?

My answer to you is to get aftermarket gauges!
It is a well known fact that the stock gauges on these cars are basically just "on/off" switches and are not going to show any accuracy.

Since you've replaced the sending units, then your next bet is the gauges themselves.

If you don't have a lot of money, some cheapo gauges from AutoZone will work for now. If you have money to spend then get a full set of AutoMeter gauges and call it a day.

[hartley88]

I had a similar problem.. i had to take out the instrument cluster and clean the connection to the temp gauge... it worked for me and i haven't had a problem since...

[Bullitt95]

Originally Posted by toyman

I'll go out on a limb and guess the problem is an engine grounding issue. Battery to engine and engine to chassis.

Make that two of us going out on a limb.

[Hanzou]

Well I actually have the same problem so I'll help test out the gauge issue for you. My gauge slowly started reading further and further to the right until it finally made it all the way to the right and that is where it stays now, car on or off.

About the same time my fuel gauge started going wacko also, it never reads correct always some random reading. I just fill the tank all the way up and reset the tripometer to gauge for myself how much gas I should have.

I'll take my gauge cluster out tonight or tomorrow morning and clean up the contacts. I'll let you guys know if that can resolve either of these gauge issues without replacing the temp sender or fixing a bad ground.

LOL, of course afterwards I am going to replace my temp sender and check my grounds even if the gauges do return to something closer to normal.

[uglyryder]

ok well i have aftermarket gauges and i didnt like having the aftermarket gauges along with having the stock gauges in the cluster that just sat there and did nothing. and on top of that the shade tree mechanic that had the car before me had them wired up in the most dangerious way possible not one wire nut dasy chaned to toggles and so on and so on. i plan on getting a custom cluster from flordia50 at some point but until then my OCD was driving me crazy having 2 oil, 2 temp and 2 tachs and it was really stupid that the way it was wired both tachs were working.

[Hanzou]

You won't believe this

Well, everyone except Hartley88 probably won't believe this.

As I said I have been having a small overheating issue with the mustang. Fan does not come on at low speeds so at idle or in traffic the car will heat up quickly. I had a few leaks in the radiator so when it started overheating instead of troubleshooting I figured I would just replace the raidator which was leaking anyway. Then I read a bit on the forum and decided to just go ahead and do the water pump and thermostat at the same time. Problem was not solved by any of that still had the problem with overheating but I had it nailed down to the low speed fan not coming on.

Well I come in here and read about Uglyrider's gauge issue and figure why not be a guinea pig and help test this out, seeing as how I had a problem with my temp gauge anyway or in addition to the overheating.

So.... I take the gauge cluster out and I'll be darned if the Fuel and Temp pins are shorted together. How in the world does that happen? So I straiten the ver flimsy pins out and reinstall the gauge.

Guys, everything clears up. Fuel gauge works correctly now, temp gauge works like normal again, and the dag on fan comes on at low speed when the engine temp gets to ~210*. It didn't overheat today at all, test runs all over the place while doing the weekend errands.

I am happy but wow that was an interesting fix. I will never FORGET this one.

Hartley88 I owe you one

Uglyrider, hope this helps you out somehow.

[uglyryder]

Hanzou glad you fixed your problem, ill have to give that a try tomorrow when i get off work. was you talking about the harness?

[Hanzou]

The pins are on the back of the gauge. I should have taken some pictures while I had stuff apart. When you unplug the harness from the gauge and take the gauge completely out you can check everything out. The pins are on a plastic tab and they seem to move out of place easily. It will be obvious if they are not straight or are touching.

[uglyryder]

ok im gonna do this today after i get my new seats in, i didnt get a chance yet.

thanx
Jon

[uglyryder]

so i took the cluster back out and im not sure what to look for, so i take the cluster out and then i take the actual gauge out of the cluster, because i was just looking on the back of the cluster.

[Hanzou]

On the back of the cluster. You don't have to take the cluseter apart. Some of the pins are labeled, Fuel / Temp etc. My pins were shorted where the connector plugs into the back of the cluster.

On another note I noticed on mine that there seemed to be a lot of corrosion from I guess moisture in the dash. Do you see this on the back of your cluster?

How did the prior owner wire up all those guages? He had to have spliced something somewhere. I figured for sure you might find something wired weird or something loose or crossed.

I really should have taken a picture when I had my cluster out.

[uglyryder]

i didnt have any corrosion where the wiring harness plugs in. the aftermarket gauges used different sending units so they were wired with there own harnesses to the new sending units.

[spdjnky_42]

Could have a stuck t stat and a little low on fluid. Fill up and check w/ a laser reader. Also make sure the new sender wire is not touching anything.