94 f150 stalls when you punch it, dumping soot outta the exhaust. ran fine before my friend let some wanna be install a stereo in her truck, brings it back barely running.

fuel filter....not new, but seen much worse
fuel pump...working,dropped the tank to check it and changed the strainer
plugs...were black and sooty and the exhast will leave a thick soot stain on the driveway after running only a few minutes.

i cant imagine what this guy could have done while installing a stereo, but this girl is stranded and about to be fired. im trying my best to help her, but my experience is limited. im a plumber,not a mechanic, although i do have a good working knowledge of autos. can change an engine, clutch, tranny, any pumps etc.. but my diagnostic abilities on autos after 1980 ?

any help would be appreciated ..if you need plumbing advice ,im your man!

 

First thing would be to check for codes.

Does the CEL come on?

 

Beyond the CEL, check the Oxygen Sensor? Check for weird wiring to it's circuit, maybe stereo guy wired to it?

Or out right replace it.

If the Computer doesn't know what the engine is doing, it'll sit in a 'drive home mode' by dumping fuel in ***** nilly causing the symptoms you describe.