narib2008

Hey Guys,
I purchased my 97 gt about a month ago.Ever since i have gotten the car i have tryed to figure out what is with my coolant temp gauge.The gauge when driving normally only reads about 1/4 of the way.However if you let the car sit...it seems to eventually get up to the 1/2 way mark.I replaced the thermostat originally because it sounded like a thermostat issue.However it did not make a difference.Thinking maybe i got a "bad" new thermostat.I removed it today and put it in water to test it out.It opened at 195 and closed at about 185.This is pretty much right on target for a new stock thermostat.So i ruled that out.I was wondering what you guys could think it could be otherwise.I found out by playing with the two coolant temp sensors the one on the drivers side seems to be used to control a/f ratio's and send a signal to the ECU???While the one on the passenger seems to send a signal to the gauge?Anyone have any idea on how to test these sensor's?Maybe the resistance they are suppose to be when functioning properly?Or could it be another issue?Thanks

Chris98Gt

What do you expect to happen, when your driving you've got that extra cooling effect so it'll run cooler, when sitting theres no extra air flow till the fan comes on. Sounds like its working fine to me.

Lowtryx

Yeah, honestly it doesn't really sound like you have a problem. You have heat, and it's on the low side. Frankly, it sounds quite efficient? :P

Is your coolant level up to your cold fill mark?

narib2008

Yes im not loosing any coolant and i have heat.No problem there.Im just worried that im running a little rich and the car is not getting the best gas mileage it could be.When driving the needle on the gauge goes to about "N" or "O" on the "NORMAL" indicator.I noticed in my 96 gt it pretty much stayed
at the "M" all the time.I just jumped my sending unit harness and the mechanical gauge inside the cluster seems to be functioning properly.Im gonna data log the coolant temp tommarow and see how it fluctuates.Im probably just being to **** about it(and ford probably uses a crappy gauge with a real time rheostat instead of a more modern average rheostat(like gas gauges use)

ESABATM

Change the sending unit. Some sending units on the 4.6 in the mid 90's weren't up to par. I had a 95 T-Bird with the same issue. Changed the sending unit with a new Ford unit problem fixed.

That sending unit has nothing to do with the fuel IIRC.

97gold

mine does it and i have a 03 engine in mine