Finally broke down and read the EEC codes

[PanamaExpat]

So I finally got around to sticking a light bulb on the thing to count the flashes. I am fairly certain the CEL is burned out as it has never come on. If I am reading the codes correctly I am getting a 32 (EGR test fail) then 75 (BOO Brake on off signal shorted to power) and a 22 (MAP or BARO signal out of range). The 32 may be the reason I get some light stumble and an occasional stall when I drop off the throttle while driving with the AC on.

So if i am reading this right (32) something with the EGR isn't working right. I am thinking it might be the solenoid. I will test that in a few and see.

For the BOO code (75) I have no idea so unless someone knows I'll be Googling for a while to try to get a handle on what could cause this.

For the MAP (22) I am figuring that since everything is basically redone it probably relates to something wrong with the EGR system as I just cleaned up and reused the original. I didn't even know my 94 4.0 had a MAP.

Mind you all of these codes could be in error if I am reading it wrong.

Suggestions, solutions clues? Anyone?

Well not sure at all now.... The 75 code suggests that the brake lights are stuck on.... Not so as they work just fine. ????

Maybe I should be looking at 3 digit codes.... 327 still indicates EGR or DPFE issue. Most likely DPFE.

522 Neutral switch is not working and I am aware of that.

 

[adsm08]

94 doesn't use MAP but it did have BARO. That is more likely to cause a stumble thab the egr system


Postin' from teh Galaxy

 

[PanamaExpat]

Thanks ADSM.... Should I be using the 2 or 3 digit codes?... I may be reading them wrong. I added a couple more insights to my OP before I saw that you had replied.

 

[RonD]

Check you trailer light hook ups, they often get corroded and show as a short.

The '94 4.0l should have a MAF sensor on the air cleaner/air plenum it can throw that code I believe.

The EGR valve can be tested with engine at idle, remove it's upper vacuum line and replace with one you can suck on or use a vacuum pump on, when vacuum is applied engine idle should drop and even stall the engine, this means EGR valve is opening with vacuum source, and if idle is smooth with no vacuum then it is closed all the way.
The vacuum lines for the EGR are very important, small cracks or spongy lines can effect the ability of the PCM to control the EGR

Here is a thread regarding the EGR system for a '94 4.0l
http://www.therangerstation.com/forums/showthread.php?t=25206

 

[adsm08]

You can also test the egr vac solenoid by unplugging bthe electrical connector and putting your finger over the egr valve end of the line. Any vacuum at all indicates a bad seal in thr solenoid.

Postin' from teh Galaxy

 

[PanamaExpat]

Thanks guys I'll have a look at it again tomorrow. Let you know if I find anything.

 

[SenorNoob]

'94 I would think would have 3-digit codes as the '92 ECU I used in my swap does. Wouldn't think Ford would go backwards on that.