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06 Short idle Lope after startup then hazes bad

6.3K views 23 replies 6 participants last post by  sledneck  
#1 ·
Every time I start the truck it'll idle great with no noticeable haze for a max of 20 seconds. Then it'll do a short "lope cycle" literally like I flip to a lope tune for 3 seconds then flip back but after that lope cycle the blue haze comes on bad. Its definitely raw fuel. I noticed when I had my torque app on rail pressure was 6k before the lope, after the lope it would drop to 5kish and stay there. balance rates are listed below.I did replace #7 with a low mileage used one and wouldn't get more than a block before I'd cover the whole road in white smoke, bad fuel knock, and the truck would shut off and not re-start until i put the one I took out back in. Then it'll run like it does now (lope & blue haze) but I can drive it all day. 3,6,& def 7 are out of spec but are they that far out that they'd cause a lot of haze? And, whats causing the lope? I can say that it hazes a lot less if I drain the filter and fill it back up with 100% stanadyne until the concentration get diluted again with incoming fuel.

#1: -1.7
#2: 1.7
#3:-2.5
#4 -1.2
#5: .5
#6: -2.5
#7: 4.2
#8: 1.3
 
#2 · (Edited)
i would try the gm injector cleaner first and see if that helps...i use the stanadyne treatment all the time since new and no problems...if the injector cleaner dosent work then it time for injectors....scott...i notesed that u have a 2006...is that ally or lbz the reason i ask is that the lly has a harness problem by the alternator were the wires break or rub through.... and needs to be ice picked search ice pick here and you will see what to do...scott
 
#4 ·
Already ran the gm cleaner through it and didn't get any change. It's just odd to me that I get zero haze until the truck runs that short lope cycle. As soon as it's done with that is when the blue haze comes on.
 
#6 ·
Oh yea, I'm definitely sure it's not the vanes cycling. I'll take a video tonight and post it if I can figure out how to do that! I know all of these haze a bit with the CAT deleted but I don't think mine is within the "normal lbz haze" group.
 
#7 ·
here are a few videos from tonight. The first one is of the weird lope. You can hear it at around 33 seconds. It doesn't haze real bad in this because the fuel filter is full of 100% stanadyne. The second video taken from under the truck looking back at the exhaust is after it was idling for 5 minutes or more to show the normal amount of haze after the stanadyne in the filter was diluted enough with incoming fuel. Is that lope coming from a bad tune? Truck doesn't have efi live, or any type of canned tuner that came with it. Doesn't rule out one of the plug in, re-flash, and unplug style tuners though I guess.

Lope cycle video- https://www.youtube.com/watch?v=Ou0w54_IO4g

Idle Haze Video- https://www.youtube.com/watch?v=0naSuoSHZLE
 
#9 ·
my bad, changed both to pubic.
 
#12 ·
The lope is whats got me confused lol. The haze isn't a huge deal, what bothers me is mine doesn't haze a bit until after that lope. Does yours haze right from startup?
 
#13 ·
Yep, I thought that was odd too. Its always done that as well. Takes that long for them to close, and they never move again at idle. Come up to a light, they're closed like that. Rev it up, idle comes back down and they're closed until I shut it off, and restart it. Then itll wait another 2 minutes to close 'em back up.
 
#15 ·
It's got 335k on it.
 
#16 ·
Yes engine light is on for a few glow plugs, and I've got a trans code P0960 for a shift solenoid and a U0100 lost communication with ecm.
 
#18 ·
Not deleted , just blocked
 
#20 ·
My 2003 Ram with the HEMI had the same kind of a lope, and it was always about 15 seconds after firing it up and would do it for 3-6 seconds or so then stop. Never figured out why, but never was a problem either.
 
#21 ·
Codes will come right back, I'll get an occasional maf code but not all the time. Truck has done this ever since I've owned it but I don't drive it a lot. I got such a good deal on it I couldn't pass it up. Don't drive it much because of these issues bit. Per the PO, it's done it ever since he had it as well. I can deal with the haze, that #7 is out so I plan on replacing 3,6,&7 all at the same time.
 
#22 ·
little more digging today. I've got a P0118 ECT circuit high input. I put a new sensor in it and no change. I just shrugged it off and was planning on digging further after injectors. From the research i did today, that ECT has a hand in a lot of different communications for these trucks. I do get a bad fuel knock that comes and goes (stays more than goes), but I always attributed it to the bad balance rates of #7. I can wiggle the ECT connector wires and my dash gauge will read accurate for a few seconds and get a noticeable idle rpm increase until it goes back to reading 160 and idle back down. Thoughts on that possible having to do with the idle lope?
 
#23 ·
Fixed- stumbled on a thread with a bad coolant temp sensor. Replaced mine today... no bad haze, no more short lope cycle , and the turbo vanes moved right after startup, not 2 minutes later.