Temp gauge in 90 GT very...

[93 LX]

I have a 90 GT Vert with a temp guage that wont go over the 1st "tick" when running. I find this odd considering once I was on it hard and could smell that the eingine was hot but the guage never moved. I replaced the sensor with a JY piece but that part looked new and the end was clean.

i have not driven the car but at idle the guage never moved past the 1st "tick" once again. So if the guage is bad how do you go about changing it?

BTW I noticed this difference in the guage package from this car to my 93. The oil pressure guage in the 90 is marked numbers where my 93 is just marked H-L. Is this normal in pre 93 Fox Stangs?

Thanks..

 

[HISSIN50]

A new sender from the parts store would have been 4 bucks.

Anyhow, get a real gauge. The stock gauges were not calibrated or accurate enough to be of any use.

Good luck.

 

[93 LX]

yeah I get that but they should be some what usable for a stock, unmolested 5.0L. I do not expect it to tell me the exact temp but I expect it to be in the normal range when the engine is warm and when the engine gets hot I expect it to go to the high range. This is how my 93, 86 and 82 work in that fassion. BTW the 82 seems a bit more accurate then you would think. 190 is in the middle which is where it runs all day under heavy trips down the 1/4 mile 160 just crusing around. Unless the autometer guage is bad too.

I am not going to start installing more guages in a totally stock and to remain stock PCH Cruiser. This car isnt even going to get headers or exhaust. I still have the cover for the dist. and what not. The only thing its missing is the coil cover which is on order.

 

[93 LX]

A new sender from the parts store would have been 4 bucks.

Free from the jy! LOL I was there for other items as well. Picked up a fender, bumper cover for my 86....

 

[HISSIN50]

The simple fact is that the stock gauges are not much more like warning lights. They have tremedous hysteresis built into them because if a gauge actually moves accurately, new owners run to the dealership every week because the needle changed positions.

FWIW, the stock temp gauge in my '88 reads 35* too cool at 190*F. Not what I would call accurate or useful.

If you dont want to add gauges openly in the cockpit, you could install one someplace discrete (glovebox, etc) or what I have done is put electronics on plates under the dash. The plates have cabinet hinges that allow the plate and device to fold up and out of sight but I can also fold it down and see what's going on. Since none of this is permanent, unless you enter concours car shows, it would work.

Another option is a rad cap with a gauge in it. This is easily swappable before shows and would allow you to try and calibrate the stock gauge. Or install a gauge under the hood.

Just some random ideas. I personally don't feel comfortable without decent instrumentation. Then again, it's over 100* today in the desert so this stuff is more important to me than folks in cooler locations.

Oh, the point about the sender was to get a new one. I dont especially trust senders and sensors that have been sitting and rusting in J/Y's, Motorcraft or not.


Good luck.

 

[93 LX]

Look I get it, stock guages suck. I do not have them in my race car but they are fine in a street car , one my daughter will drive. Any more distractions then her phone, music and what not wouldnt help. All I want to know is if anyone has changed the stock guage before and whats involved.

 

[Saleen0679]

Disconnect the temp sender and put a 10Ω resistor between the wire and ground. Turn the car to the 'on' position. You should see the gauge rise smoothly all the way up.

 

[93 LX]

Disconnect the temp sender and put a 10Ω resistor between the wire and ground. Turn the car to the 'on' position. You should see the gauge rise smoothly all the way up.

This will test the guage? I think the guage is low but cant prove it. Does the resistor have to be large in wattage?

 

[Saleen0679]

It will test the sweep and input of the gauge by simulating the sending unit's upper end. Small resistor will work. I've used 1/4W with no problem. You will know if the gauge is capable of giving a high reading. If the gauge doesn't sweep high then you know you have a wiring or gauge problem.

To test for a low reading you would use a 74Ω resistor.

 

[93 LX]

welp it looks like i have something to do next weekend LOL

 

[LiquidGT]

Also, check the ground strap that goes on the back of the drivers side head to the firewall. Then check the number 8 pin on the white 10 pin connector on the back of the intake. You might as well clean the all the pins and bend the female pins on the connector with a nail or something for better contact. (If you do the black side the car might idle better.)

I suppose you have a thermostat in the engine, I know it sounds stupid.

I tried everything in this thread and more and my temp gauge still acts funny with the headlights on, anyway I ended up getting a real temp gauge.