Hi just joined and i have a question about rolling idle on my 2002 duramax. Same idle in gear or not idles up and down and is getting worse and power is down. If anyone has a idea what's going i sure would like the help.
thank you
Lefty

 

Stock or? Welcome to the site!

 

when was the last time the fuel filter was changed

 

Hi yes it is a stock motor,and don't know when the filter was changed last.
thanks Guys i do need help

 

try changing that first, could make it run better... could not. but is cheap and easy to do.

check the oil and see if there is any diesel fuel in it or if it smells like diesel at all

 

could it be his injectors cause duarmaxes had a problem witht them nd they have a 7 year 100000 mile warrnty if they go bad.

 

its a 7 year 200,000 mile warranty not 100,000

 

Actually guys its not a warrenty its a special service policy covering injector failure due to ball seat erosion or cracked bodies on all trucks equipped with an LB7 model engine.

If they fail, ALL EIGHT get replaced free of charge. Doesnt matter if you have a programmer or anything, they get replaced free of charge. Dont let a dealer charge you anything. They cant. There is no $100 deductable because it isnt a warrenty.

You are covered for 7 years and 200,000 miles. You can obtain the information on when your truck was put into service by getting a VIN report.


Now Start by changing the Fuel filter.

Then if that doesnt fix it. I would smell the oil looking for hints of diesel. See if you notice a rough idle and harder longer starting. Also look for blue smoke at idle. Then if you can find a buddy with EFI Live, a Predator, or acess to a Tech II, to check your balance rates. To do this right, get the truck up to operating temp, set the parking brake and put it in drive. Dont hit the throttle. Then look at the balance rates. Anything +/- 6mm3 means you have a bad injector. Or possibly a blown HG, popped injector cup, cracked piston or bent rod but not likely on a stock truck.

Basically what the balance rates are showing is how much that injector is having to compensate to keep everything consistent and smooth.

Then the next step is having the dealership check the return rates since the new TSB says bad balance rates arent good enough anymore.

If the injectors check OK, I would say its a Bad Fuel Pressure Regulator.

THese are the 3 things that will cause surging idles.

---AutoMerged DoublePost---

Actually guys its not a warrenty its a special service policy covering injector failure due to ball seat erosion or cracked bodies on all trucks equipped with an LB7 model engine.

If they fail, ALL EIGHT get replaced free of charge. Doesnt matter if you have a programmer or anything, they get replaced free of charge. Dont let a dealer charge you anything. They cant. There is no $100 deductable because it isnt a warrenty.

You are covered for 7 years and 200,000 miles. You can obtain the information on when your truck was put into service by getting a VIN report.


Now Start by changing the Fuel filter.

Then if that doesnt fix it. I would smell the oil looking for hints of diesel. See if you notice a rough idle and harder longer starting. Also look for blue smoke at idle. Then if you can find a buddy with EFI Live, a Predator, or acess to a Tech II, to check your balance rates. To do this right, get the truck up to operating temp, set the parking brake and put it in drive. Dont hit the throttle. Then look at the balance rates. Anything +/- 6mm3 means you have a bad injector. Or possibly a blown HG, popped injector cup, cracked piston or bent rod but not likely on a stock truck.

Basically what the balance rates are showing is how much that injector is having to compensate to keep everything consistent and smooth.

Then the next step is having the dealership check the return rates since the new TSB says bad balance rates arent good enough anymore.

If the injectors check OK, I would say its a Bad Fuel Pressure Regulator.

THese are the 3 things that will cause surging idles.