Fox Issues

Alright, I've been having a few issues RECENTLY..

Car runs super rich! Throws Lean codes. Sputtering very romp...romp...etc idle (not surge)

Pulled the intake as it seemed to be leaking causing a vacuum leak. Figured that was my rich, lean code issues.

Got it all back together , installed a msd 6al2 while I was at it.

Got it all back together. Still have the same issues! And I noticed when i run codes it shows **6cyl** now . Makes no sense!

Also cylinder balance test comes back just fine..
 
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disconnect the MSD..check all vacuum lines and that all bolts are torqued down. As Mike said, what are the actual codes.. Could be a lot of things. Do you have any smog equipment disconnecct?
 
Sorry guys, been trying so many things. And nothing has fixed it. Tried multiple ECU's.

Now the cylinder# is just blank, no number at all.

Checked pump out, injectors, fuel pressure. Made sure no injectors are leaking and the fpr isn't leaking or bleeding off, pulled engine harness, went through all the wiring, tested from end to end. All good. Tried 3 mafs, new Distributor etc.

No emissions are on the car, egr is plugged in with no vac line, been this way over a year without issue.

Only thing I get is lean codes, and emissions but I always had ems codes, but the car runs rich! Idle and low rpm,cruise issues

Changed the oil 6 days ago. Smells of gas already. Only drive the car 30-40miles a week.

I'm just at a loss, getting really close to going carbed lol
 
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You need to take the msd off first to verify you didn't mess something up wiring it

It was the same issues before hand, unhooking the msd makes no change.

Codes are emissions and lean (02s) but the car isn't lean. Rich by a long shot!

Currently have the eec harness out on my kitchen floor, 2 pinouts I can't find a end connection to.

Searching as we speak for what these wires are for.
 
I chased my tail on an issue like this. My car idled bad....the fumes would run people out of my shop and got lean codes.

The problem ended up being my o2 sensor harness was shredded on my k member. The computer thought it was lean so it dumped fuel.
 
I messed with the o2 harness about 6mos ago when I had issues, got it fixed. So I didn't really look into it this time.

I know right now 2 wires are dead in the eec harness.. can't find an 89 pinouts to figure it out.
 
What pins are they ? I can take a look in the am in my service manual. Sure someone here knows them by heart.
 
So the ecu harness checks out, I didn't know a few wires had to be tested at a certain resistance, due to the resistor in the wire.

Also pulled the 02 harness and tested for shorts, and connection. It's perfect
Engine harness I did last week.

So with that being said, Who's got some ideas ? Could an 02 throw a lean code, but be bad and cause rich running. And blowing the same capacitor in the ecu ?
 
Only situations can see where car runs rich but throws lean codes are if the o2 sensors themselves are bad. They are telling the ecu to fatten up the mixture and are not responding.

What year is this car? It's not a MAF conversion or 2.3L conversion is it?

Actual code numbers would be a big help vs description.


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It runs rich for sure. Raw fuel.

It's a built alum headed 306.

Tried different injectors,fp, fpr, mafs, tps,iac, ECU's. Messed with every harness. All have tested good.

Figured the lean code but running rich may also be vacuum leak, pulled intake and re sealed everything.

Issue is still present