The Over Heating Of A 5.0 Mustang Issue

check the fan clutch, pressure test the cooling system to see if you have a leak.

160* is too low drop a 180* in.also the stock guage is not very accurate so dont be to concerned.

I'm having a simular problem (its why i plan on replacing my engine) my situation my car uses about a pint of water on a 40 mile trip......then if I push it hard about a quart of water.

system has been pressure tested.....nothing
new radiator.....(3 core)..................same problem
new thermostat.............................same problem
new radiator cap............................same problem
Hoses all good, and heater core is bypassed. still problem presist!

fan clutch seems to be working.......and as long as I have plenty of water it never overheats..........just looks kinda cheesy to have to put water in my car in the work parking lot everyday and then have to worry with same deal before I leave home in the mornings.

The 94-95's have a HORRIBLY anemic radiator (it is about 3/4 of an inch thick). Couple that with the fact that the low speed fan does not come on till ~208*F and high speed at ~226*F and you can see that you heat the system up and it has a hard time cooling back down.

An upgraded radiator can help, esp if you have a stocker which has likely seen better days (in terms of heat transfer).

I am not sure what you have fan-wise. If you still have the stock fan control mechanisms in place for your new fans (via the ECT and CCRM), you can wire in couple manual switches.

Pin 14 on the CCRM would receive fused 12 volts (for low speed) and Pin 17 would receive GROUND. For this reason you cannot use a DPDT switch. And dont have both fan switches on at the same time. And dont go from off to high speed. As always, use your meter before making any connections or using the switches.

A real temp gauge is a must, unless you have a TwEECer and can interpolate the stock guage via the tuner.

More info on when you run hot and at what temps would help us to provide more precise recommendations.

Good luck.

My 95 Cobra did that when it had a blown headgasket. It was very slight so it didn't always affect the car. It took me a while to figure it out.

With 115F ambients you need more radiator and more fan. And you REALLY need a real temperature gauge that will tell you what temperature you're actually running. Changing thermostat temperature does absolutely nothing to change the fact that you can't reject enough heat with your radiator and those ambients. In fact, the lower temp t'stat makes your system less efficient than it was with the higher temp stat. If it can't reject enough heat to keep it at 195F, how do you expect it to reject the EXTRA heat necessary to get it down to 160F?

Follow the guy's recommendations above - 1) more radiator, 2) more fan, 3) quality temperature gauge.

Check this out for fan/controller options -- it's the best stuff out there for controlling an electric fan if you decide to go that way. www.dccontrol.com