My age old problem...SOLVED Please Read!

[Synned]

This is where the differences in 94-95's and Aero foxes comes into play.

The 94-95 processor is load based, and to try to make the car run cleaner, there's too much timing and too little fuel.

A quick and dirty way to try to enrichen things is to do the IAT tricking. Sure it aint correct to do, but it can help. A 180* t-stat isn't factory correct, but it can make for a nice compromise..... this is the same kinda thing in my mind (When temps cool off, Joe will hook his IAT harness back up to the IAT I bet).

Joe, I'm glad to see you checked the resistance values for the thermistor - my recollection had been that there was a ton of resistance in some of the readings (the curve is parabolic as I recall).

Anyhow......... Enjoy!

Exactly. I'm just glad I'll be able to go to the track during the summer without worrying about the car running like a dog.
As soon as summer ends, the IAT will be back operating.


Thanks to everyone who has helped!
Joe

 

[jrichker]

Shouldn't the computer know the actual air temp going into the engine? This seems like something that wouldn't work well in all conditions, or else ford would have done this from the beginning. BTW what does a 33k and 10k translate to temp wise for the ACT?

Pin 25 ACT signal in. at 50 degrees F it should be 3.5 volts. It is a good number if the ACT is mounted in the inlet airbox. If it is mounted in the lower intake manifold, the voltage readings will be lower because of the heat transfer.

Pin 7 ECT signal in. at 176 degrees F it should be .80 volts

The ACT & ECT have the same thermistor, so the table values are the same.

Here's the table: The values are +/- 15%, so don't get worried if your readings vary a little bit.

Voltages are measured across the two connector pins of the sensor with the sensor connected.
68 degrees F = 3.02 v
86 degrees F = 2.62 v
104 degrees F = 2.16 v
122 degrees F = 1.72 v
140 degrees F = 1.35 v
158 degrees F = 1.04 v
176 degrees F = .80 v
194 degrees F = .61

Ohms measures at the computer with the computer disconnected, or at the sensor with the sensor disconnected.
50 degrees F = 58.75 K ohms
68 degrees F = 37.30 K ohms
86 degrees F = 27.27 K ohms
104 degrees F = 16.15 K ohms
122 degrees F = 10.97 K ohms
140 degrees F = 7.60 K ohms
158 degrees F = 5.37 K ohms
176 degrees F = 3.84 K ohms
194 degrees F = 2.80 K ohms

 

[pb_paulie_b]

Congrats! I love reading tech threads that end like this

 

[Synned]

You think you're happy

I have noticed the car was running a little warm today, dunno if it was related or not.

 

[795.0pacecar]

I was having the same problem, but I may have fixed it. I found that an ignition power wire that goes to the EEC relay was dissconected. I traced the wire to be what powers most of those sensors.