Good luck. Hopefully that's all.

 

If you haven't bought a tuner and tunes yet I recommend getting a EZ Lynk tuner and tunes from GDP. Running that setup on my 2012 F-250 for about 15K now and it works great. Check with OSTSAZ.COM.
Also if you haven't replaced all the glow plugs do it now!

 

did you figure out your over contributing issue? I have this on cyl 7

 

Sorry I did not get a notification when you posted. I have not figured mine out.... I decided just to keep running it till something happens. Few injectors didn't fix it. Tried glow plugs. I have not tried another tune but it drive fine. Any chance you figured yours out?

 

Hi there has anyone figured the issue out? Ive got a low contribution at idle in cylinder #2 , truck has a loud exhaust pop/thump but still drives idles starts great , ive already checked the valve trainer minus pulling the heads to check the valves and all checks out.

 

This is a different issue than mine I believe. I never figured mine out just plug it in and keep driving till it goes. Yours sounds like an exhaust valve issue. Early 6.7s had issues with burning valves....that may be your problem

 

[QUOTE=Bigkell;18848654]I just bought this truck and I have no history on it. 2011 f350 6.7. Blowing white smoke mainly during start up and taking off from a stop. Showing codes for #3 and #4 contribution. Exhaust smells like unburnt fuel. Buzz test was good. Compression test was good. Had it hooked up to Ford tech laptop. Shut off computer timing compensation and #3 and #4 drop off the chart and it starts running like crap. Turn computer back on and idle smooths out.

Changed #3 and #4 injectors and replaced both fuel filters. No change. Got a tip that maybe the return line is plugged. Blew tons of compressed air in it attempting to dislodge something. Seems to be flowing freely. No change. Starts right up and idles perfect. Seems pretty smooth when revving it up especially in higher rpm. When taking off from a stop it knocks and kinda surges into 2nd gear. Turbo surges also. On the freeway it's smooth and powerful. Passes cars with easy but does knock pretty bad at first when you put your foot in it. A little hesitation, then clears out.

The engine is fully deleted. No egr. Straight 4" pipe. Unknown tune.

Any ideas?[/QUOTE

 

Dieselboss. Mine is kinda the same, when air temp is below about 50 degrees I get a misfire for cyl 8 and it smokes till it warms up....then it runs great. My injector tested good and compression is good. I even replaced the injector and glow plug just to be sure. I also have a slight "tick/knock" under load all the time. I gave up and just gonna run it till it blows. Let me know if you find the issue....maybe glow plug?

 

I highly suggest pulling your valve covers and have a look. I had been having cylinder contribution codes and a shudder and reduced power with the trailer on. No smoke that I noticed but full intact emissions equipment may have had something to do with that. Very frequent regens though. I pulled the valvecovers and found a mess. Check out my thread "Injector Issues" Mostly on the drivers side which sounds like your issues are on as well.

 

I have a similar issue that began when I went into water above the hood to rescue a guy in the middle of Hurricane Harvey. Truck stalled but I was able to get it started again and drive out. I was in the "deep" water for less than a minute. Insurance totaled it and I bought it back with a salvage title. Now it's got a felony record but drives fine.

Mine throws the Cyl. #4 contribution code. Used to throw cylinder #3 also but that has stopped. Replaced #3 injector once and that cured that one. I've replace injector #4 tow or three times and I will still get an occasional contribution code for that cylinder. I usually clear it and then I doesn't come back for several months. Like others, I get the light "Diesel" knocking during acceleration at around 2000 RPM through 2500 rpm. Otherwise truck runs fine. Truck idles fine, accelerates fine. It's been this way for 4 1/2 years and 40,000 miles. Multiple long trips. If it were going to blow, I figure it would have by now. It's the price I paid for doing the right thing in an emergency. That said, if anyone figures it out I would be real interested in finding out what it is. This is the most information I've found on the problem.

 

how many miles are on the engine?

gone are the days of diesels lasting a million miles.

 

Truck had 70k on it when the incident occurred. I'm at 115,000 now. It's not a mileage problem. And the problem hasn't gotten any worse over time.

It does seem to be a bit m9re pronounced when it's cold outside. Of cold is relative when you live in Houston like I do.

 

I got the same thing going on. Contribution cyclinder 8. Mine started hard. And idled weird like it was missing and had a knock when under load a little bit. Had shop put all 8 injectors in and it did same thing. Doesn't always throw the code but runs like ****. Took cab off, pulled valve cover, turbo and driver side head and everything looks great. Cams good heads good. Don't no what 2 do next

 

I gave up on trying to fix mine. Itll smoke and miss till it warms up (anything under 45 degrees). I have what sounds like an injector knock while under load, runs good and starts up every time. I decided im gonna run it till she blows or maybe next winter I'll pull valve covers off. Am interested in if you find a problem with yours though!

 

This sounds just like mine. I've chased this for 4 years and 40k+ miles. Replaced the injectotvtwice with little to no change. Mine is cyl 4. Occasionally throws a code (every 4-6 months-). I reset it and it stays off for several months but symptoms remain consistant. I get a knock/rattle under load between 1500 and 2000 rpm. More pronounced in cold weather (under 45 *F). With rough idle it the colder temps until engine is warmed up.

Otherwise, it runs and idles well. I've taken the position that if it hasn't blown up in over 40k miles of use, this probably isn't fatal. Just did an 8 hour round trip this weekend with no issues.

I'd love to know if someone ever does figure their's out.