Cold miss/stiction diagnostic

dieseldoc · February 23, 2013

My 2006 F-250 has a cold miss/stiction on a cylinder or two I believe. If it is plugged in it is barely noticable, but if it cold soaks for 4-8 hours without it just hammers for about 10-20 seconds before it clears up. I am running a mobil 5-40 synthetic oil changed every 4-5000 miles. I have checked my glow plug system and all is well there. It is a fuel knock sound, once it runs about 10-20 seconds it goes away and is fine the rest of the time. I am wondering what type of testing you use to find these type of issues?

mchan68 · February 23, 2013

Power Balance with weak cylinder contribution strategy disabled.

Brad Clayton · February 23, 2013

That and a cold injector buzz test.

Aaron · February 23, 2013

Failing both of those you can hit each exhaust port at the manifold with an infrared thermometer and see which holes are cold.

Matt Saunoras · February 23, 2013

I'll be the first to say update your FICM calibration to the latest and greatest.

I used to have the latest calibration on my truck and never could figure out which injectors had stiction issues. It would romp for a second then clear up on a cold start, just quick enough that power balance couldn't catch it.

Then I got stupid and figured out how to roll back to the original cal it came from out of the factory. Guess what? No inductive heat on the old ficm calibration. Now I've got a dead #5 cylinder for atleast 10 seconds on a cold start PLUS two others on that bank that are low. Posted Image

It's amazing what an inductive heat strategy will do, it really does work wonders.

dieseldoc · February 24, 2013

My truck still has the old rattle cal in it. The cylinder contribution test with ids is that a comparative graph with all cylnders or screen with each cylinder and a +/- value next to it(similar to per dels on a 7.3)? I have not used an ids, since I dont have one. So I am trying to see if the tool I have access to has a similar test. Maybe the best option will be to take it in, and have them diagnose it, replace the offending injector, and update cals. I really would prefer to diag and fix myself but with this type of issue may not be possible. I work mostly on 7.3s or 6.0s for head gaskets, egr cooler work. I have turned down 6.0 driveability stuff because I dont have ids so a little green with finding the cause on this issue. thanks for the help