84 Mustang check engine light issue

http://www.wisconsinvip.org/WivipPublic/PDF/Downloads/noncom052108.pdf

If the check engine light was on before you disconnected the battery you will need to address that issue before the monitors will reset. If there was no check engine light driving a combination of city and freeway for a day should reset all monitors

There is a diagnostic procedure in the factory service repair manual for engine light lit ,no codes . Did you take it to ford dealer ? MIL - is referring to check engine , service engine soon etc...

• MIL always on when engine is running (no DTCs):
• MIL circuits

• For Focus, Mustang, Town Car, Continental, LS6/LS8, Escape, Windstar, F-150, Expedition and Navigator/Blackwood:
• Instrument Cluster, Section 413-01 of the Workshop Manual.
• All Others:
• GO to NB1

SERVICE ENGINE SOON indicator After the engine is started, the SERVICE ENGINE SOON indicator will prove out for a duration of three seconds. If the instrument cluster does not receive a message from the PCM within five seconds, the instrument cluster will illuminate the SERVICE ENGINE SOON indicator and log a diagnostic trouble code (DTC).

• An indicator is inoperative/always on - SERVICE ENGINE SOON

• Circuitry.
• Bulb.
• Instrument cluster.
• PCM.

• GO to Pinpoint Test P .

PINPOINT TEST P: AN INDICATOR IS INOPERATIVE/ALWAYS ON - SERVICE ENGINE SOON CONDITIONS DETAILS/RESULTS/ACTIONS P1 CARRY OUT THE INSTRUMENT CLUSTER SERVICE ENGINE SOON INDICATOR ACTIVE COMMAND Trigger the HEC active command MIL.

• Did the SERVICE ENGINE SOON indicator illuminate?

Yes REFER to Powertrain Control/Emissions Diagnosis (PC/ED) manual.

No INSTALL a new instrument cluster; REFER to Instrument Cluster . CLEAR the DTCs. REPEAT the self-test.

Not sure if you fixed your stall issues but....have you looked at the pip signal on your fox mustang? My 1987 mustang gt was doing the same thing it got to the point where the car failed to start. It was the pip sensor located in the distributor. I removed the distributor and took out the pip sensor replaced it with a oem replacement re-timed the car its ran great since. I also went to the boneyard and grabbed a few tfi and installed one on my distributor most mechanics suggest you do this when you replace the pip sensor. Hope this helps someone dealing with this issue on there 87-95 mustang gt. Took me about 45 minutes

There should be a 10amp fuse in the fuse box for the instrument panel that powers the light. The light is grounded by the computer.
Have you checked the fuses in the passenger compartment ?

check all connections to starter or your voltage regulator

The light is controlled directly by the computer so if your car runs, it isn't a fuse. It just needs a bulb put in it.

If you bought it used someone probably disconnected the hot wire or removed the bulb in an attempt to pass inspection.

a wheel sensor on the side that hit, has had a cable cut or is smashed

not a solution, a suggestion,
a broken or cut cable on the sensor would suggest to the computer that the wheel is locked, no movement, a skid

the no data error can be contributed to a bad interface cable or the scaqn tool was configured wrong and therfore could not connect to the ecm. I would recommend having a scan done again by a certiefied volkswagon tech chances are the mechanics used the wrong adapter cable or reader card. your smog problem could be that your evap canister is clogged therfore gives a bad reading.unfortunately you have to have a scan done but try an independant small shop that delas exclusively with foreign cars such as porche andd mercedez. the will have the correct scan tool and will be much cheaper than a dealership. your cost should be no more than 50 dollars US ... please rate this. thanks