Looking at buying an lly but...

TubbedTruck67 · 12-29-2012, 11:20 AM

Im not sure of a few things. Ive done alot of reading on here and still not sure wat to do. The truck is an 05 lly ccsb 4wd 198k it worrys me tho because it is bone stock and smokes like its tuned way up! It black smokes at all times... It also shakes the hole truck when it idles but only part of the time. Has some fuel knock also which sounds terrible is there no way to get rid of any of that? I guess my question is where do i start to begin to know wat is wrong with this truck to fix the rough idle and constant black smoke? It seems to run ok other than the periodic idle issue and its still getting good fuel milage. It belongs to a buddy and im driving it to fig out wats wrong ang wether i wanna buy it or not but im not sure at this point. Its already had a cp3 and 2 new injectors at the dealer to try to fix this problem w no luck. And i bleed the fuel system and did get a little air and the fuel knock got better but still not gone.. Bleeding the fuel system did seem to get rid of a high rpm surge the truck had when you had your foot in it. Its a nice truck id like to have it and down size from my lbz one ton but not sure if this trucks worth it any ideas? Thanks

jacobdewey · 12-29-2012, 11:30 AM

Don't. Unless it's too good of a deal to pass on.

Check the air filter, make sure it's clean and put on properly.
Check for loose intercooler boots or any other boost leaks in the system.
My guess is you may also have a chance that the egr valve is stuck open.

Hope that give you a starting point.

**Brennan** · 12-29-2012, 11:31 AM

Check the ficm harness around the alternator bracket for chafing

Sent from my iPhone using AutoGuide.com App

TubbedTruck67 · 12-29-2012, 11:40 AM

I already checked the air filter its new ac delco put in at the same time as the new cp3 and two new injectors. Fuel filter is new also. I dont have any way to check balance rates or does that not sound like the problem? I have read about the harness issues but havent had time to look into that yet i will asap tho. If it was egr stuck open wats the best way to test that?

**TDIpowered** · 12-29-2012, 11:52 AM

find another truck to buy

TubbedTruck67 · 01-01-2013, 03:23 PM

Checked the balance rates today. 2 and 7 were .0x and the other 6 were all over the board number 3 being the worst anywhere from -3.9ish and i saw it at -6.x and the others all in the -2.x range and then one in the -3.x range. Pretty safe to say thats why its smoking black at all times???

MTL_Dmax · 01-01-2013, 04:45 PM

Quote:

Originally Posted by TubbedTruck67

Checked the balance rates today. 2 and 7 were .0x and the other 6 were all over the board number 3 being the worst anywhere from -3.9ish and i saw it at -6.x and the others all in the -2.x range and then one in the -3.x range. Pretty safe to say thats why its smoking black at all times???

Was your actual vs demand rail pressure holding steady at idle?

That truck will likely need a few injectors (some are leaking), but a bad FPR will make it look much worse than it might otherwise be.

TubbedTruck67 · 01-01-2013, 05:59 PM

Yes rail pressures were both steady at around like 1200-1400 i believe? But the fuel flo was idleing at like 3800. Comparing to a buddys truck thats way off is that from the leakn injectors causing it to flow more fuel and thats where the constant black smoke is coming from? This truck has had a new cp3 but im not sure if the fpr was done at the same time or not.

MTL_Dmax · 01-01-2013, 06:25 PM

Quote:

Originally Posted by TubbedTruck67

Yes rail pressures were both steady at around like 1200-1400 i believe? But the fuel flo was idleing at like 3800. Comparing to a buddys truck thats way off is that from the leakn injectors causing it to flow more fuel and thats where the constant black smoke is coming from? This truck has had a new cp3 but im not sure if the fpr was done at the same time or not.

If it was a brand new CP3, they usually come with a new FPR too.

Sounds like some of the injectors are just leaking and returning too much fuel.......you'd need to do a fuel return test to see which were NG.

TubbedTruck67 · 01-01-2013, 07:07 PM

Ill have to see wat cp3 was put on it but i knew the remans from a parts store came with a new one but figured that was probly extra at the dealer..

How do i do a leak test on the injectors?

12-29-2012, 11:20 AM	eBay Motors #1 (permalink)
TubbedTruck67 Junior Member Join Date: Nov 2007 Posts: 27	Looking at buying an lly but... Im not sure of a few things. Ive done alot of reading on here and still not sure wat to do. The truck is an 05 lly ccsb 4wd 198k it worrys me tho because it is bone stock and smokes like its tuned way up! It black smokes at all times... It also shakes the hole truck when it idles but only part of the time. Has some fuel knock also which sounds terrible is there no way to get rid of any of that? I guess my question is where do i start to begin to know wat is wrong with this truck to fix the rough idle and constant black smoke? It seems to run ok other than the periodic idle issue and its still getting good fuel milage. It belongs to a buddy and im driving it to fig out wats wrong ang wether i wanna buy it or not but im not sure at this point. Its already had a cp3 and 2 new injectors at the dealer to try to fix this problem w no luck. And i bleed the fuel system and did get a little air and the fuel knock got better but still not gone.. Bleeding the fuel system did seem to get rid of a high rpm surge the truck had when you had your foot in it. Its a nice truck id like to have it and down size from my lbz one ton but not sure if this trucks worth it any ideas? Thanks

12-29-2012, 11:31 AM	eBay Motors #3 (permalink)
Brennan Some Newfie with a dmax Join Date: Aug 2010 Location: newfoundland Posts: 3,595	Check the ficm harness around the alternator bracket for chafing Sent from my iPhone using AutoGuide.com App __________________ 06 lly, Black, Levelled, Efi by rob, 5" Etc.

12-29-2012, 11:52 AM	eBay Motors #5 (permalink)
TDIpowered Hang it!...Fire! Join Date: Aug 2009 Location: Tacoma, Washington Posts: 4,251	find another truck to buy __________________ Max - 07 LBZ ECLB LOWERED! Plugged, Rerouted, Blocked, PPE Mod, DE 5 inch, DE 3inch DP, EFI Live DSP-5 by IDAHO ROB, Insight, Raptor 150, Transgo Jr, Nicktane, PROEFX Steel Roll Pan, XD Revolvers -24 Offset 20x10 w/ 305/50 Nitto 420s, Alligator Sleeves, Belltech 3inch drop shackles, T Bar bolts all the way out, DDM Tuning 6000k Low/3000k Fog, and about 50lbs of Zipties

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12-29-2012, 11:30 AM	eBay Motors #2 (permalink)
jacobdewey DuramaxForum Veteran Join Date: Nov 2009 Posts: 1,390	Don't. Unless it's too good of a deal to pass on. Check the air filter, make sure it's clean and put on properly. Check for loose intercooler boots or any other boost leaks in the system. My guess is you may also have a chance that the egr valve is stuck open. Hope that give you a starting point.

12-29-2012, 11:40 AM	eBay Motors #4 (permalink)
TubbedTruck67 Junior Member Join Date: Nov 2007 Posts: 27	I already checked the air filter its new ac delco put in at the same time as the new cp3 and two new injectors. Fuel filter is new also. I dont have any way to check balance rates or does that not sound like the problem? I have read about the harness issues but havent had time to look into that yet i will asap tho. If it was egr stuck open wats the best way to test that?

01-01-2013, 03:23 PM	eBay Motors #6 (permalink)
TubbedTruck67 Junior Member Join Date: Nov 2007 Posts: 27	Checked the balance rates today. 2 and 7 were .0x and the other 6 were all over the board number 3 being the worst anywhere from -3.9ish and i saw it at -6.x and the others all in the -2.x range and then one in the -3.x range. Pretty safe to say thats why its smoking black at all times???

01-01-2013, 05:59 PM	eBay Motors #8 (permalink)
TubbedTruck67 Junior Member Join Date: Nov 2007 Posts: 27	Yes rail pressures were both steady at around like 1200-1400 i believe? But the fuel flo was idleing at like 3800. Comparing to a buddys truck thats way off is that from the leakn injectors causing it to flow more fuel and thats where the constant black smoke is coming from? This truck has had a new cp3 but im not sure if the fpr was done at the same time or not.

01-01-2013, 07:07 PM	eBay Motors #10 (permalink)
TubbedTruck67 Junior Member Join Date: Nov 2007 Posts: 27	Ill have to see wat cp3 was put on it but i knew the remans from a parts store came with a new one but figured that was probly extra at the dealer.. How do i do a leak test on the injectors?

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