my 96 f250 is running very rich and spitting smoke at idle, once driving it runs beautifully but at idle it runs like a POS and it sucks way too much gas even for a 460. The exhaust reeks like gas. I replaced the o2 sensor and put a new distributor in it but it hasn't made a differece. I was thinking the EGR or the map sensor could be giving me the problem? Anyone have any opinions or past experiences? Any help would be great, thanks!

 

I have the same problem with my 1990 F350 460EFI E4OD trans so I will be interested in what fixes the problem I have not done anything about mine as I Run on LPG most of the time mine starts on Petrol then switches to LPG and now I have just removed the motor to rebuild
but I would be looking at the MAP sensor and O2 sensors firstly as they send the signals back to computer to control air/fuel ratio also I would check the vacuum line to the MAP sensor make sure it is in good condition and leaking

 

I replaced the MAP sensor and it fixed the problem. The truck runs much better and doesn't suck fuel like it did.

 

Don't guess pull the codes and check fuel pressure.

 

It needed an o2 and distributor anyways but the MAP fixed the idle issue, truck runs 100% now