87 Ford Ranger

[kgates]

Having problem with running rich on 2.9 liter. Once warm the engine idles ruff. Under 2/3thirds to full throttle engine runs properly. Once you back off of throttle to cruise it starts blowing black smoke and missing.
I think I have replaced every sensor on the vehicle,the O2 sensor, map sensor, EGR valve and sensor, swapped computers, checked the voltage on the TPS sensor.I am at a loss of where to go next. Any help would be appreciated.

 

[Bondo]

Check the orange wire that grounds behind the block on the passengers side. Check for bad wire and clean up where it grounds. Could be the culprit.

FPR maybe?

Also the coolant temp sensor could be bad. (Its right in front)

Im still trying to get my 87 to stop running rich. LOL