B-Well

car is a 91 318. 90k original miles

car has been problem free for 2k miles. then all of a sudden misfire thoughout rpm range.

replaced fuel pump (mine was whining so it was needed anyway)
replaced plugs. double platinum
replaced wires. bosch 7mm premium
replaced coils.
replaced ecu

the second cylinder coil is sparking at the coil and with plug in the end of wire it sparks, but when in the cylinder it does nothing. unplugging 1,3, or 4 causes it to nearly die but unplugging 2 has no effect.

unplugged maf but still idles rough

RandomTask

Injected? could be a down injector.

B-Well

i just pulled it in the garage to check it. im hoping thats it.

RandomTask

If you know you're getting spark, do a compression test. Provided that checks out, you're not getting fuel. Injector is either clogged or coil on the injector is fried (check the resistance)

B-Well

one bad injector and the rest were very clogged. large pieces of rust gunk came out after soaking and cleaning.

jt223539

Upgrade them to mustang injectors while you are in there.

tpspool

what kind of car is it?

Dough_Boy.

I have some #19 injectors out of a 5.0. Is that what injectors you are talking about?

jt223539

I believe so, I know you want #19 5.0 injectors, just not sure if you want the ones from the original mustang 5.0 or from the later 5.0 that was available in the explorers and such. I personally installed the ones from the explorer 5.0 and they are still working perfectly.

Here is a thread with more info about the injector swap if you are really curious:

http://www.m42club.com/forums/showthread.php?t=233