Bad injector?

[F14CRAZY]

Howdy folks. It's been a long while since I've posted or visited the forum at all, but I'm back.

Anyway, my '92 is suffering. Once in a while the engine will miss under acceleration. It'll shake passengers. The check engine light has been coming on and off but it stayed on today. I swung by Advance Auto Parts and had a dude put a scanner on it but it was "out of range" or something along those lines.

However, this problem goes back farther. Maybe a month ago (I haven't driven it much) I noticed the engine stuttering/missing. It took a bit more turning for the motor to start, too, and there's a "putt" from the exhaust. I checked most everything, and got to the spark plugs and found that the spark plug of the cylinder in the middle of the driver's side bank (number 5?) was crudded up (a Bosch Platnium 4 with a few thousand miles of it). I picked up a set of plugs from Advance Auto Parts and replaced that plug.

It got a lot better but still wasn't really running like it should. I'm finding that the plug is covered in raw fuel. I've driven it a little by swapping that plug with another plug in that bank so it'll clean itself off.

Now, I'm thinking that my problem is that the injector for the supposed number 5 cylinder is stuck open. I've ran a few tanks of gas through it and used a bottle of Chevron Techron cleaner but it didn't help. I plan on replacing this injector. Is this the right thing to do? I would replace them all but they're about $65 each from there, times 6 and this motor is kinda loose anyway . Any other suggestions?

Thank you.

 

[MrShorty]

So, the guy at Advance couldn't get any codes from it?? Probably didn't know how. You can pull codes yourself using nothing more than a paper clip. See www.troublecodes.net/Ford

If an injector were stuck open, it should be noticeable using a fuel pressure guage. Pressurize the fuel system (I find it's easiest to use the fuel pump test lead in the self-test connector) then shut the pump off. An injector that is stuck open will allow the fuel pressure to drop off fairly quickly (there are other possible causes, too, so this isn't definitive). Note that a fuel injector can be stuck open if there is a short to ground in the wiring on the computer side of the circuit. Make sure the wires to the injector are intact before assuming the injector itself is bad.

 

[F14CRAZY]

Thanks for the advice Mr. Shorty. I'm pretty sure that the injector was stuck open, because earlier, I didn't relieve fuel pressure (I forgot) before removing the fuel lines on the fuel rail and hardly any gas came out.

But anyway, I replaced the injector. I took it for a few spins and I'm pretty sure it's good. No more stutter or CEL. Thank you.