Engine Codes 31,34,35, etc. help

I can almost guarantee it's the ACT sensor. Ohm test it.

Daliceo said:

Just pulled the codes on my foxbody. It’s throwing codes 4 and 8(cylinder misfires?). Also codes 31, 34, 35, 64, 45, and 95. I have deleted the smog pump and equipment. The lower intake and upper is typhoon.

It has inconsistent idle, smells VERY rich, dies out on idle sometimes or when in neutral while turning etc. Idle drops very low and fights to stay on.

Any guidance on what it’s throwing?

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When you delete the peripherals you cause problems...If you disable their functions and keep the solenoids plugged in they dont cause any interferrence issues...For the EGR alls needed to do is make a blockoff gasket and install it because once you delete the sensor the timimg becomes locked just like riding around with your spout connector unplugged..

If you dont wanna go the tuning chip route I suggest adding the 3 resistors needed to meld the EGR circuit ,Thermactor circuit plus TAB and TAD solenoids..When done right the resistors combine all of the circuits on pin #46 to sensor their sensor power to give the circuits the right resistance to trick the ECU something is there............

As far as the other issues....Try this...I know that you think your power and grounds are perfect and if so post some pics of your wiring..

Grounds are very important in an EEC-IV system as the system is riddled with RF interference everywhere........The EEC-IV system uses a double grounding method to measure resistance between a single dedicated ground from the ECU on pin #60 that has no other grounding points attached into it to its grounding location just behind the battery going into the unibody....That location has the least interferrence and close to the battery which absorbs RF interferrence,

Pin #40 has the MAF circuit ground plus just grounds the ECU internal and gives the ECU a "Clean Ground" or the "Cleanest Ground Possible" to put it in a better term...

The grounding wires look like these...They need to be cleaned up...Once those wires get dirty and stop grounding they cause the dirty grounds that are grounding the sensors to the engine block to take over and the RF interferrence wreaks havoc on how the ECU reads sensor voltages etc and throw codes causing you to replace parts for no reason sometimes.....


This is how an EEC-IV system is supposed to be grounded............The 02 sensor isnt shown but the 02 sensors go to the cylinder head and HEGO ground for #49 goes to the intake manifold.Speaking of 02 sensors...They must ground perfectly to the exhaust and the exhaust to the engine block really good.




Pins #37 and 57 are voltage sense wires and power the ECU too but the EEC relay has an effect on that too because the older the relay gets the more ineffective it becomes at properly transferring the high capacity 12v load needed to supply the ECU and if your relay is older than 10years;-REPLACE IT with a Diode Protected one no matter if it still clicks.....

So in essence once you also replace the starter solenoid for one with diode suppression built into it plus ground the solenoid body really good to the unibody then replace the + battery cables between the battery and the starter then create a STAR point grounding system where the Engine block is the center with the battery attached to the engine block point then the K-Member attached to the engine block too and battery attached to unibody where the ECU grounds are with a 10ga wire. I used a 4 ga wire in my pickup...

Most of the harsh RF interference will be absorbed into the K-Member then into the battery and away from the main ECU grounds allowing the ECU to do its thing without getting irritated........



If you have a G3 alt you need a 4ga ground wire at the rear of the alternator case to the K-Member too but at a different location from the engine block mounting point.

Next thing to do is make sure youre running a non-ccd TFI of you have a 5 speed and that the wire going from the ECU on pin #4 to pin #2 on the TFI plug shows atleast 22kohms....If not youre gonna have to add one or replace the resistor...Ford made so many mstakes over the years like carelessly leaving out the 22kohm 1/2 watt resistor and that causes TFI modules and sensors to go haywire when you take your car on long rides over an hour.......LOL



Heres what it looks like when its installed by Ford but they also can do defunct and when they fail they fail to open so if you get 0.00kohms replace or install a new resistor.....



you can get 100pcs for $5.00 on amazon.....Get some shrink tubing and cut wire #4 IDM circuit wire heat a tad then thread the needlelike ends into the wires and use shrink tubing to seal the connection...no soldering required



Good Luck getting the issues ironed out...I know mine are........LOL

Whats funny is when people with cars with EEC-IV systems say their cars are running good but state that at startup their cars do the idle surge and fluxuation dance between 30 seconds up to a couple minutes then levels out then in restart revs to 1800-2000 rpms then slowly climbs down to idle........Not Mine....LOL...

Mine starts up and revs up to 1600rpm's and stays there with no needle fluxuations for about 240 seconds then the idle drops slowly by 50rpms every 2 seconds to my desired idle of 1200 without the needle bouncing around or hearing the engine idle surging with IAC trying its damndest to keep the engine smooth...LOL

The reason why their cars are doing that is because their dosing their IDM circuit and TFI module with unfiltered power.......LOL

That 22kohm resistance is crucial.....One time in my F250 5 speed I had a resistor installed but the dist failed so I bought a replacement and the TFI module was the CCD type and those modules are for automatics and have the resistor built in so now having 2 inline resistors gave me 44kohms of resistance also a computer controlled dwell against the ECU's wishes that caused chaos upon and with-in the EEC-IV system...LOL

Good Luck


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