Engine Operating Way Too Hot No Explination..

[jays91gt]

Guys I have a 91 GT and recently swaped out the upper and lower intake with a GT 40 set up. I also used the 97 Explorer injectors and installed a new t-stat. I bought the car with all the smog stuff gone including the EGR (installed a bypass to get rid of the CEL) Anyway now when I get on the highway or gun it hard my temp goes up to about 75% and stayes between there and 50%. After its parked the system is about 6 inches low and hot. Ive pressure tested and its fine. I burped it and replaced a couple sensors. No CEL.

GT 40 Upper and Lower Intake
97 Explorer Injectors

This is all Ive changed what could be causing this? I used proper torque specs and sequence. This has been on going for about a month. Ive posted on "mustangforums" but I keep getting deuch bag responses. Im about to take the car in to the dealership. So this is a last ditch effort. I apologize for the detailed explination. If any of you have been through this or have any idea please chime in.

 

[Tonys96Cobra]

So are you losing coolant? Or just running hot? The stock temp gauge is not the most accurate thing in the world, Im assuming that it is running hotter than it did before the intake swap? You may still ahve an air bubble or gotten something into the system causing a clog. If you could borrow or buy a cheap temp gauge and hook it up that would help to see what the actual temp# is.

 

[jays91gt]

So are you losing coolant? Or just running hot? The stock temp gauge is not the most accurate thing in the world, Im assuming that it is running hotter than it did before the intake swap? You may still ahve an air bubble or gotten something into the system causing a clog. If you could borrow or buy a cheap temp gauge and hook it up that would help to see what the actual temp# is.

Both actually. I have a thermometer and a new guage sensor and its pretty accurate. I burped the system on jacks real good many times with the same results.

 

[jays91gt]

would runing lean cause this? Reason is my new fuel pump sounds weak when I turn the key on. Could this be the problem?

 

[2000xp8]

unlikely.
Losing coolant is either a leak or a blown Head gasket.
No drips under the car? Heater core doesn't leak? Water pump?
What kind of thermostat are you running?
Use a Mr gaskets 180 degree.

If your budget permits, get an autometer mechancal temp gauge. The stock setup is screwy regardless of sender, because of the crappy wiring in our cars.
My temp gauge used to rise when i turned the lights on.

 

[jerryD]

how many times have you filled the coolant back up after a "hiway" run? you might be loosing coolant through the intake and burning it. even though it is a new gasket, did you line it up correctly with the head? it may have slipped over a little to an intake port and mite be just enough when you get to higher rpm's the water pump puts more pressure out and it is getting by.

 

[Ranchero5.0]

Make sure the T stat is in correctly first... Spring goes to the intake, not the hose. Pop the upper hose off and feel for the pointy end, not the flat bump where the spring goes, That usually causes what you describe.

Jamie

 

[Roland69]

and also never forget to change the oil after removing the intake....you will get coolant in the oil