Check Engine Light-EGR flow insufficient

[farmertracks]

Last week I went on a 3000 mile trip with 2006 LLY pulling a trailer with a car on it to Indiana, and hauling a small tractor home from Iowa. On the way there, about half way through Kansas, the check engine light came on right after getting fuel and heading up the on ramp to get back on the interstate. The next morning, I took the pickup to the dealership in a town in Iowa. The diagnosis was the EGR flow was insufficient. GM had a bulletin out on this I was told, and that the cause was a calibration issue. They did a learn procedure on the EGR valve, and did the update and sent me on my way. Exactly 1200 miles later, the darn check engine light is back on. I have not had a chance to go back to a dealership now that I am back home in Colorado to see if it is the same code.

My pickup is equipped with a 6 speed manual tranny, AFE stage 2 intake, and straight-piped factory exhaust, both the converter and the muffler have been removed before I got the pickup, and those are the only mods to the pickup, no chip or anything. I should mention this pickup only has 18000 miles on it.

My question is, does the free flowing exhaust and intake have a part in this code, or are they the cause of it, or should it not make a difference? The dealership that checked it out said that neither should make a difference on that code. I am wondering if I need the EGR blocker plate and fingers stick to make the light stay off, and what effect does the blocker plate and stick have on mileage for the guys that have installed it? What do you guys think?

[Bobo]

Last week I went on a 3000 mile trip with 2006 LLY pulling a trailer with a car on it to Indiana, and hauling a small tractor home from Iowa. On the way there, about half way through Kansas, the check engine light came on right after getting fuel and heading up the on ramp to get back on the interstate. The next morning, I took the pickup to the dealership in a town in Iowa. The diagnosis was the EGR flow was insufficient. GM had a bulletin out on this I was told, and that the cause was a calibration issue. They did a learn procedure on the EGR valve, and did the update and sent me on my way. Exactly 1200 miles later, the darn check engine light is back on. I have not had a chance to go back to a dealership now that I am back home in Colorado to see if it is the same code.

My pickup is equipped with a 6 speed manual tranny, AFE stage 2 intake, and straight-piped factory exhaust, both the converter and the muffler have been removed before I got the pickup, and those are the only mods to the pickup, no chip or anything. I should mention this pickup only has 18000 miles on it.

My question is, does the free flowing exhaust and intake have a part in this code, or are they the cause of it, or should it not make a difference? The dealership that checked it out said that neither should make a difference on that code. I am wondering if I need the EGR blocker plate and fingers stick to make the light stay off, and what effect does the blocker plate and stick have on mileage for the guys that have installed it? What do you guys think?

It is a pretty common issue with a LLY/LBZ setup like yours. I think PPE tuning can get rid of the code....and I am positive that EFI Live can get rid of it.

[Duramaster]

Hey BOBO, do you have some pics of your twin turbo LLY that you can post? :D

[carco]

The finger stick and block off plate have had no noticable mileage effect nor any driveability issues. My dealer suggested adding the stick and plate after reprogramming for the EGR codes and ck engine light due to straight exhaust and cat conv falling off. See Kennedy for the stick and plate. bob...............

[Kennedy]

Removing the cat causes this issue. You can band aid it with the Fingers stick (splicing wires) or we can take care of it as well as other things in the ECM programming

[Bobo]

It is a pretty common issue with a LLY/LBZ setup like yours. I think PPE tuning can get rid of the code....and I am positive that EFI Live can get rid of it.


There is video of it in this thread:

http://www.thedieselpageforums.com/tdpforum/showthread.php?t=29722

[steak2k1]

Kennedy

wouldn't it be also advised to block the EGR as well as installing the fingerstick. ? why throw gunk and soot into the intake. I know it's environmental and all, but it can't do the motor any good. While at the same time the addition of exhaust gases would likely reduce the overall amount of fresh air and O2 going into the motor over a given period of time. ..NO.?;)

your thoughts..?

rgds
stk