This is really getting on my nerves. I have a 95 F150 5.8 EFI. I started having this problem about 2 months ago or longer,the issue is a VERY rough idle when its cranked. Its seems like its choking out on me. The battery gauge will go down when it starts to choke out, and the entire front of the truck shakes...like its starving for gas or something.( plus now i actually smell something on the lines of perhaps gas...or something...while its choking out and im giving it gas, i smell something) It has to be cranked like 10-15 mins before i leave and warmed up just so it wont do this on the road( which it will hesitate badly if its not warmed up prior to departure) Things that have been replaced are the 02 censer...the idle air control valve, Fuel filter**( fuel filter was replaced by my mechanic**..I replaced the others myself. and a complete tune up new wires plugs. I do also have a problem w/ rusty looking water in the radiator, i dont know if that may be causing any of this (doubtful) but i was planning on getting a can of radiator cleaner and flusing it myself...besides that this is a very irratating problem and any help would be gratly apprecaited...oh, and My mecahnic could NOT run the codes because of it being a 95, so i bought one and it told me that the 02 censor was bad, besides that...i'm lost. The only 2 things i can think of is a ground cable connection problem, or the FI needs to be cleaned...after i get her warmed up for about 10-5 mins of running the idle up, it eventually settles down and drives fine....but this is very irratating
Someone please help, Thanks so MUCH!!!!!

 

You might look for an EFI fourm. Sounds like it could be your MAF needs cleaned replaced maybe. I would read the stored codes. Either go to a parts place and have them do it or you can do the paper clip method that is outlined in most repair manuals. The radiator problem is seperate. Good luck.

 

Have you tried clearing the computer? Probably won't do anything but never hurts to check. Usually an engine won't look to the o2's until its warmed up anyway, so thats probably not your problem. Maybe check out the coolant temp sensor. Maybe a vacuum leak that seals its self once the engine is warm? A bad ground or clogged injectors would probably show up all the time. Might go to a junk yard and try swapping out ECU's and see if that does anything. Thats all I can think of right now