Anyone here ever had a bad fuel injector?

[downzero]

I have a bad misfire that I've had a hell of a time diagnosing. It's in the #5 cylinder (driver's side middle).

I pulled out the plug the other day and #5 was soaked with gas, leading me to believe that the fuel injector is bad.

Truck has a lot of miles on it so anything is possible, but before I even pull the upper intake to swap the injector, I'm curious if anyone has had to replace an injector in one of these trucks before, since injector failures are not all that common in any vehicle.

I was thinking about just swapping the injectors from the right side bank to the left to make sure the problem moves as well. The passenger side injectors are (relatively) easy to get to compared to the driver's side.

 

[jhammel85]

If it's firing order is the way I think it is, That #5 cyl is right at the fuel pressure regulator. Check the fuel pressure to make sure that regulator isn't riching out that cyl.

 

[shane96ranger]

What are you working on there bud?

 

[JP02XLT]

Sometimes you can unplug & plug the injector with the truck running, and it will clean itself from "hard Stop & Start" and it might fix it if it is just sticking. Its cheap and worth a shot before you change it out

JP02XLT

 

[adsm08]

Pull the fuel rail out, keeping it connected to the lines, get all your injectors in the rail and secured to it with zip ties. Key on, look for drips out of the injectors.

 

[downzero]

I swapped the #5 injector with #2 and the misfire didn't seem to move. Seems I'm back to the drawing board.

Truck is a 2000 Ranger, 3.0 flex fuel.

Everything is great besides it having a completely dead cylinder.

 

[shane96ranger]

What else have you done? Did you put a new plug in it when you checked it? Have you tried new wire(s)?

 

[McCormack]

Coil pack?

 

[shane96ranger]

Before you get to the coilpack, you would want to swap the wire right next to it and see if the misfire moves. Might not hurt to try that now.



Sent from a Commodore 64 using a 300 baud modem

 

[jhammel85]

How about a compression test. Have you done that? If that checks out OK, then it must be ignition related.

 

[downzero]

Update for you guys:

Of course I did a compression test, and the cylinders are all pretty weak, but even. While my diagnostics on this one did have some bonehead twists and turns, that was the first thing I did after checking all the plugs.

I ended up pulling the intake and swapping an injector over to the other side, which did nothing (surprise surprise). Injectors are fine.

What I failed to do was check the obvious--the plug wires--because they were less than two years old. Turns out one of them was cracked all the way to the core. But it wasn't #5--it was #4; the computer lied to me. I had changed the #5 plug wire and in the process, shocked myself with the broken wire. Problem solved!

I also seem to have managed to create an exhaust leak on the EGR pipe when removing the upper intake. I can't really tell where that's coming from yet, still working on that one.

But the best news is that I have 6 cylinders again!

 

[jhammel85]

Good to hear it's OK again! Thanks for following up by the way...so many threads out there never have a conclusion.