LB7 slow runner

[ChazMo]

I am new to this forum!:hello:
I have a 03 LB7. Owned for about 9 months. I recently put a PPE Hot programmer on it. I did this in hope it would help it get off the ground. It has always been slow from the start. When pulling my 4 hours trailer at times i have had to put it in 4wheel low just to get it up small hills.
Now that i have the PPE on it, it doesn't appear to be much better. Still very slow off the line. once it gets moving seems to be better. Absolutely no smoke and i have it currently on 4 but even on level 6 still nothing. anyone have any ideas on why and what i can do to make it run like it should.

 

[Mike L.]

Fuel filter?

 

[ChazMo]

I changed the Fuel Filter last week.. Intake filter is clean also

 

[2004LB7]

Whats your maf reading?

Was it tuned prior to adding your PPE?

 

[ChazMo]

It was tuned prior. It still has the aftermarket security system on there which i cant get off too. i was told that the ECM was reset. I dont know what my MAF is reading? how do i know this?

 

[THEFERMANATOR]

You need to get a good scanner on it and diagnose it. You need to make sure the ecm is seeing the apps requesting power, check to see if actual rail pressure is following desired, see if the maf reading is going up as airflow changes, and do a check of the overall health of the vehicle. Putting a tuner on an engine that sounds like it has an issue is only going to make things worse, if not damage something. The lb7 is a little slow on initial takeoff because of the standard non vgt turbo, but it shouldn't be horribly bad even stock for power. A tuner is not going to fix an isdue with the truck if you have one. You could easily have a wastegate stuck open, low rail pressure, or even something as simple as a maf sensor installed backwards(its happened). Without scanning it, you have no idea whats going on.

 

[ChazMo]

I understand that putting a programmer on it not knowing is a risk. I have never owned a Duramax and have heard that they do run good. After doing research i found that the PPE is a good Programmer for them. Can i check if the waste gate is stuck open? I know smoke tells a "story" so with absolutely none while the PPE is on, is kinda strange too, Right? My cummins runs amazing and is a coal train.. Appreciate your feedback.

 

[Burn Down]

I wouldn't think it's the waste gate seeing it has no smoke. Try removing the MAF sensor and cleaning it with MAF sensor cleaner and verify its in the proper direction. As the ferm mentioned you'll need a decent scan tool to look at MAF readings. Stock air intake or aftermarket?

 

[ChazMo]

AFE stage 2 intake. The Boot right off the filter seems a little worn..

 

[Burn Down]

Dry or oiled filter?

 

[ChazMo]

Dry filter

 

[THEFERMANATOR]

I wouldn't think it's the waste gate seeing it has no smoke. Try removing the MAF sensor and cleaning it with MAF sensor cleaner and verify its in the proper direction. As the ferm mentioned you'll need a decent scan tool to look at MAF readings. Stock air intake or aftermarket?

If its not making boost, then the maf won't go up enough to let it fuel, and no fuel means no smoke. I'm not sure how smoky the new ppe stuff is. Somebody let me try out his old one, and I took it out in a hurry. WAY to much smoke for me.

Since you say it has an afe filter, check the maf to make sure its in correctly as you can install the maf either way in an afe intake.

 

[NC-smokinlmm]

Check for oil dilution, could be bad injectors not making desired rail pressure bc bodies are cracked or returning too much fuel.