2003 lb7 rough idle and smoking like a big dog? - Chevy and GMC Duramax Diesel Forum
01-04.5 LB7 Duramax Powertrain Discussion of components that are directly involved in the power production and all that is needed to get and keep the truck moving . Engine , Transmission, Etc.

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post #1 of 3 (permalink) Old 04-10-2012, 04:56 PM Thread Starter
Join Date: Apr 2012
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Question 2003 lb7 rough idle and smoking like a big dog?

Just this morning it started idling pretty rough and is smoking when its idling and when you take off it seems to clear up after going for a little while. Im pretty sure it's an injector problem but not positive, going to check it out tomorrow night on the pluse width. Is there any other thing that might be causing this and also is it going to hurt to drive it more? I've checked to see if it's making oil and don't think it is, also I've checked the air filter and put some fuel additive in it too but still on a smoking......any ideas please hit me hit me up!!! Thank you
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post #2 of 3 (permalink) Old 04-10-2012, 06:05 PM
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Sounds like injectors to me. Check your balance rates and that will help you out alot!! If your not getting diesel in your oil then you are okay to drive it for awhile before you hurt anything.

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post #3 of 3 (permalink) Old 04-12-2012, 05:29 PM
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I also have an 03 LB7 and after reading all the fuel additive stuff and injector problems I added some stuff to mine......almost immediately I noticed some white smoke which seemed to load up worst while extended idling.....I thought they may have been pooched.......just finished up returning on a trip from WA state and after running 3 tanks of fuel through the exhaust is clear again and I got just shy of 25 mpg on the return trip home.......heres hoping your in luck........

03 2500 LS, LB7, CCLB

Last edited by hardtail; 04-12-2012 at 05:31 PM.
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