Heating issue, is it the EEC

Greetings,

At this point, I am not sure if I require the EEC. It is just the only part that I have not swapped on my bird in my attempt to solve a cooling problem.

Since I have absolutely no luck finding a qualified mechanic that does greater damage than good on my car, I though that I would attempt this overheating problem myself. I had verified that the following are functional and operating within specifications:

Thermostat
Water pump
Fans
Gauge

Noticed that the fans were not turning on when car began to overheat. One would turn on, however, if A/C is on. Replaced the following per Ford recommendation:

Temp Sender
Temp Sensor
Fan Relay

While troubleshooting, I noticed that when I removed the connector from the Temp Sensor, the fans “both” would turn on at high speed, which would maintain the temp. Looking into a troubleshooting guide, it reads that my next step would be to replace the EEC.

Thoughts?

Mike

I believe that the IRCM(Integrated Relay Control Module) actually controls most of the fan functions. That is the black box located infront of the airbox. I could be wrong on that though??

Thomas

The fans should not have turned on when you pulled the ECT sensor wires. The fact that the fans did turn on means that the relay module and fans are good.

How did you verify the temp gauge?
Has the car been properly purged of air? This can cause bad readings on the ECT sensor (sensor sitting in a bubble of air).


You should be able to pull ECT sensor readings out of a 94 computer with the right scan tool. Don't easter-egg it, get the data pulled from the computer.

If the computer is reading bad data then check the the wiring to the computer, both signal (ECT) and grounds. Only after you find that you can read the correct resistance for the ECT sensor AT the EEC connector and the EEC has good ground/power do you want to buy a new EEC.

Aaron

Heating issue, is it the ECC

Granted, my method of gauge verification was probably not the correct method, but I removed the climate control sensor and placed another gauge and sensor that I had in a project car into that port. I then, verified that the internal gauge and new gauge increased at the same rate. When the bird internal gauge began to display overheat, the new test gauge displayed between 190 and 200.

I figured that this would be somewhat accurate. Probably not, though.

I have another question. I pressure checked the system again to verify that I did not do something incorrect during my last test. When I began applying the pressure, I heard a "click-like" sound from the vacinity of the thermostat when pressure reached about 22lbs. Is this type of sound normal, or did it release a "sticky" thermostat?

Could the pressure check during my last check released a "stuck" thermostat and then fooled me into thinking that it opened at the correct temp?

Think that I am going to go to the dealership and pick up a replacement....

Mike