Detroit 60 misfire need help

[Brock]

2006 Western Star 4900sa detroit 60 ddec v started misfiring or fluttering, I lost alot of power. It is not smoking white or black under load, no engine codes. Here is a video in my fuel tanks when running.

https://youtu.be/GKDN3U-Ryx0

   

From DDDL here is the injector response time. The top 5 all fluctuate constantly about 0.02 max but number 6 stays steady at 0.67 and never budged.

   
   

Here's the cylinder cutouts at 1000rpm and at idle. At 1000rpm number 6 is consistently lower but I don't know if that means anything. At idle it was usually the same although in this pic number 2 was low, 90% of times I ram the test, 2 was strong. 3 was iffy and 6 was low.

Problem is I don't know how much of a spread is ok or at what point is considered low. Maybe I have another issue.

[Hammerhead]

That fuel churning Brock, looks to me like a failed injector. It appears to be large volumes of compression gasses released for the return line that is submerged below the fuel level.

I haven't worked with DDDL, my last S60 was a DDEC III & I have a Prolink, so I have zero knowledge of the software and didn't even look at those screenshots.
I've only ever worked on one failed S60 w/failed injector and it was totally dead. Based on what you're describing, I'm leaning towards #6, but I ain't telling you nothing I'm sure you e already figured out.

[Rawze]

Sometimes you have to pull the manifiold back away from the block and fire it up, look for the cylinder with the problems/ differences/compare to find the exact culprit. Watched Mr. Hag chase a similar problem like that,.. he had sent out the injectors for testing, replaced a couple of them, chased it and chased it again,.. After suggesting he pull the manifold back and firing it up, it revealed the problem injector right away. He then moved the injector to a different hole and the problem followed the injector.

[Mr Hagg]

With the # being lower on the cut out test I would run it several times and if it is lower than baseline each time Id pull injector and check it out maybe looking at bad injector for sure. Or the old fashion way let it cool down all the way start it up and place hand on manifold to see if #6 is colder than the rest. Inspec the orings really good if they look bad replace all of them...

[MommaBurt]

if it is less than 0.2 than your average, the injector is bad. i usually do the test multiple times to make sure but it looks like in your case number 6 is bad.

[Brock]

   

Changed fuel filter and got the engine nice and warm, ran test 3 times and each time was similar to this.

[MommaBurt]

with numbers that low i would say for sure its the injector. check the valve train and wiring while your in there but i bet its the injector

[Brock]

   

Well time to dig in. Valvetrain looks good, can't see any bad wires, gonna swap 1 and 6 and see if it follows.....

[redbeard]

Why your in there, is it a good time to also check the bull gear bearing?