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
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.
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?
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???
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???
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.
That seems pretty consistent with what most have seen. Both the LB7 and LLY have the same compression ratio so if must be either the emissions equipment (EGR + Exhaust) or the turbo which is the difference maker. Can't imagine the PCV makes a huge dent in MPG. If anyone had any insight on that I'd be all ears.
Well maybe it's all preferance. Stock to stock my lly and lb7 were the same power, but my lb7 would kill my lly in economy and running cool. Best mpg out of lly was 17.2, best out of lb7 was 24 mpg. All hand calcualted, driving 55-60 mph.
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