Ddec V rough idle help (DDDL snapshots)

Something is not right with the baseline on that idle test. You should have the engine up to temp, run the test 3 times back to back and average the numbers. Your air compressor or fan could have been running during the baseline sample and kicked off when cutting out. Your test at 1000 looks like a good test, but #6 is bad.

Think of the tests this way. The baseline represents total fueling with all 6 firing. When you cut a cylinder, the others work harder to push the dead cylinder. The numbers should go up because it's running less efficiently. You are looking for the number to go up at least 0.2 over baseline and all cylinders to be within 0.2 of each other. Looking at your 1000 RPM test with a 4.03 baseline, the minimum you should see on any cylinder is 4.23, so something is not right with #6. Virtually no change when it's cut means it wasn't doing anything to begin with. #3 also show a little weak, but it may be OK once you average out 3 back to back tests. With your highest at 4.69. the lowest should not be lower than 4.49.

 

Grape is right on. To me it looks like the same. Bad #6. I would look closely at rocker shaft/rocker roller on #6 when you are removing it. Lately, for my shop, it has been more stuck and damaged rockers and scored shafts than actual bad injectors.

 

If it only has the davco make sure it has the correct filter in it.. 7 micron

If by chance someone installed the wrong one damage is done.

 

Well then I think you know what your problem is then...

Fuel in davco should look like fuel. Not black.
Soot in fuel from combustion gas getting into fuel rail... that would explain the rough running also and wierd cylinder contribution on the computer.