Riddle me this...

[TheBac]

riddle me that....

What causes lots of white smoke at idle when engine is cold but none when engine is warm, the smell of diesel in the cab on occasion, and an uneven idle?


I think I know, but I have to get over to Eric's to do some tests first...

 

[Noreaster]

Is the FPR stock or modded?

 

[dmaxfireman]

hung injector or lack of compression? both result with unburnt fuel

 

[TrentNell]

hung injector or lack of compression? both result with unburnt fuel

X2 my first thoughts .

 

[stroke250]

i sure hope its not lack of compression for toms sake...

 

[CurtisEmery]

Could be bad glow plugs too. I had this issue last winter.

 

[2500HeavyDuty]

hope its nothing too bad tom, we gotta to get into the 11's man :thumb:

 

[SDP]

I'm having the same exact problem Tom, just started a couple weeks ago. All balance rates withing +/-1.5 but white smoke when its cold then clears up in a couple minutes. Noisier at low throttle and uneven idle like you said.

 

[SmokeShow]

any fuel in oil? That's another thing to help check the injectors.

I'm hoping for the best for ya. :hug:

 

[SDP]

any fuel in oil? That's another thing to help check the injectors.

I'm hoping for the best for ya. :hug:

No fuel in oil, just changed them with GM remans in February.

 

[dmaxvaz]

I have the same issues. I think the tuning has to do with it, ESPECIALLY BECAUSE OF THE FPR CHANGE

 

[RKTMech]

Injectors can leak out the tips and not show anything on the scan tool, but pulling the glow plugs, disableing the GP electrics and pull the edu relay and crank it over and look for fluid to spray from any cylinders will help to see if you have a seating problem with your injectors and then your ready for a compression test.

 

[IdahoRob]

I have the same issues. I think the tuning has to do with it, ESPECIALLY BECAUSE OF THE FPR CHANGE

If the engine didn't do it before and now does with the same tuning, I doubt tuning is causin the smoke. If the tuning changed and now smoke, then that could be a possibility.

Are you guys checking the balance rates when the issue is happening?

 

[wkinsley04]

i had this exact same issue when i bent the rods in my engine. do you still have an uneven idle once the engine is up to temperature? try bringing the rpm's up around 2000 while in park and see if the engine feels a little rough. if it doesn't feel smooth i would say theres a good possibility of bent rods.

 

[uwyo_dmax]

i had this exact same issue when i bent the rods in my engine.

Sure hope thats not the case Tom good luck with the diagnosis

 

[TheBac]

Thanks guys. Not looking for sympathy, just giving information. If I broke something, then its just part of the game. I believe we should be open about things that come up like this...as someone will know what it is, or it'll help others diagnose whats happening to their ride.

I am currently running the stock tune, and have been since the day after my last TnT a few weeks ago. I do not run around on the race tune. The truck runs just fine above an idle. It doesnt make any extra noise when going down the road, either. It does seem to make a lot more "pilot-injection"-type noises at idle, esp when cold. Power is NOT noticeably different, other than the stock tune always seems like a slug after running the race tune.

Yes, it has an LB7 modded regulator. I was finally able to get the lope out of the idle by logging the commanded/actual reg voltage at idle, and changing B1010 from there. If I set the idle voltage too low to get rid of the lope, could that cause this?

These are the balance rates from tonight, engine warm, in park.
1) -.089
2) -2.88
3) +1.69
4) -2.03
5) -1.61
6) +2.98
7) -2.22
8) +3.83

I'll get rates tomorrow AM in both idle and drive. Cold rates are ugly for a couple of cylinders. IIRC, one was +6, another was -9! I figure Im going to need injectors before next summer...and warranty was up last week. Time to start saving for that, too.

In talking to Eric last night, I described what was happening. He thought for a bit, then told me that my symptoms are the exact same as Bobo and CAP when they both bent rods.
Now that being said, my truck also smoked extremely bad last winter on startup, chugging and sputtering, then smoothed out as it warmed up....just like now. This summer I found that the drivers side glow plug rail was busted between #6 and #8, which meant only #8 was working all last winter. Thats fixed. I cant imagine that all 8 GPs are bad, and I dont get any codes for a bad GP controller.



I plan on going to Eric's next weekend, and we'll do a compression test then....and then we'll know. This weekend is booked solid already.

 

[emiller3]

Wish you luck

 

[stroke250]

incoming call tom!

 

[TIM Z]

Your a good man Todd!

Hope you get it figed out Tom. If not Eric will have to build you an early Christmas present!

 

[TheBac]

Your a good man Todd!

Hope you get it figed out Tom. If not Eric will have to build you an early Christmas present!

Thanks Tim. I wish I could say Im looking forward to Santa stopping this year, but sinking $10,000 into a new septic system later this month (bids go out tomorrow) plus the potential for this costing $3000 or so is not making me all warm and fuzzy.

This is plus the fact I dont know how Im going to tell Roni that I hurt my truck.