Misfire code (and misfire)

[Lendawg]

Oh yeah, got lots of spark, arcing to exhaust manifold when held at least an inch away.
I really don't know how to check a fuel injector. I would assume it is just a solenoid-type electrical valve. In which case, I assume you could ohm it out and compare to one that is working. As far as being clogged, I guess that would be a visual inspection. I couldn't find any specifics online as to how to test them yet.

 

[discomike]

I am wondering if you can somehow get a test probe into the injector plug and see if the ECU is allowing the injector to fire???
Mike J.

 

[Lendawg]

Well, I didn't find much about how to test the fuel injectors, so I winged it. The presumed bad one ohms at 17 ohms, and so does the presumed good one next to it. With the engine running, the voltage as measured at the connector (disconnected) is about 14 vdc as measured w/ my elenco dvm...same with the good one.
Regardless, I went over to five-o fuel injectors (website) and found a set of 8 NEW injectors for $289, and I couldn't pass it up, as they are $75-$100 EACH everywhere else. Mainly because this is my only vehicle, which limits the amount of f@#$%ing around I can do to get this thing fixed.
Time will tell.

 

[discomike]

So am I understanding you correctly, were you able to get a good pulse signal on the injector, if so that is good and the price is right.
Let me know how it goes.
Mike J.

 

[Lendawg]

Yeah, I'm guessing it's a pulse signal (I know it's supposed to be). I really wish I hadn't sold that old Heathkit oscilloscope in the yard sale many years ago. It would be cool to watch all this going on in real time.
Oh well, for now I'm just waiting.

 

[Lendawg]

Well, I changed the injectors today. It took about 3 hours, went (relatively) smooth. If I had to do it again, it would only take about 1&1/2 hours. I spent a lot of time talking to it.
Did it fix it? I don't know for sure yet. All the tests haven't finished running in the OBD, should be complete tomorrow. It does still have a noticeable miss at idle (let up off the brake slightly, and you can feel it lurch with the RPM's).
I also got my Magnacor wires today and put them on. Didn't change much at idle, but I was half pickled and couldn't test drive it yet.
One thing I noticed when I put the SeaFoam in it last week was that some of the smoke came out at the exhaust manifold/downpipe connection. I wonder if this could be contributing to the problems? If the O2 sensors don't get all the exhaust, they could over-correct the fuel for that bank.
Thoughts?

 

[discomike]

If you can get a smoke leak from the exhaust manifold, you can suck in air also causing a bad reading from the O2's.
Hey, if it is not one thing, it is another.
Hang in there and enjoy the pickle juice.
Mike

 

[Lendawg]

Yeah, I think I will take it to an exhaust guy tomorrow. I don't do exhausts. Every time my Dad had an exhaust problem, he'd say something like "How'd you like to learn how to do something new, son?" He set me up so bad, man! I have had enough rust and dust in my eyes for a lifetime.

 

[Lendawg]

Well the drive cycle completed this morning, and everything seems hunky-dory. I'm still gonna get the exhaust leak fixed, though.
It's funny, in all the misfire code searching I've done, I never came across the mention of exhaust leaks as a possibility, but it stands to reason.

Wish me luck!
Len

 

[discomike]

You when you say everything is OK, does that mean the truck is happy again, no more problems except for the exhaust leak which will effect the reading to the ECU for the air/fuel mixture?
Mike J.