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Chris (aka-Moose)
Chris (aka-Moose), Technician
Category: Chevy
Satisfied Customers: 47633
Experience:  16 years of experience
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LB7 issues I have a diesel repair shop n am stumped with a

Customer Question

LB7 issues I have a diesel repair shop n am stumped with a fuel issue
Submitted: 6 months ago.
Category: Chevy
Expert:  Chris (aka-Moose) replied 6 months ago.

Welcome, I'm Chris (aka Moose), my normal schedule online is around lunch and after dinner till early morning.

Have you monitored the accelerator pedal position sensor readings to see if there is a gradual increase shown or a sudden jump?

If you view all pids through freeze frame on a bar graph, do any readings shown a sudden spike up or down when you touch the throttle?

Customer: replied 6 months ago.
well they guy bought this truck off used car lot ..... here are the mods..... has a custom tune "don't know who wrote it" , also has a boost fuller, also has a AEM methanol injection "shooting blue windshield washer fluid" and a fass fuel pump "un regulated" I un plugged the fass pump than hit the throttle and seems like that was it so I bought a cheap reg at parts house but seems like it's not working, in the morning I'm going to try and hook fuel lines back to stock and see because isn't the cp3 only soppose to have only like 5lbs of vacuum ??? N no I haven't watch accelerator peddle for spikes I also pulled off methanol injection thinking it was it ?? Wat u think I outta try now??
Expert:  Chris (aka-Moose) replied 6 months ago.

I would for sure remove all that junk that is destroying the engine. Get the modules back to OEM programming. Then see what is going on. There is not a diagnostic path from GM to follow for a vehicle that is modified, pretty much all diag steps do not apply. I still would like you to do the inspections I mentioned.

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Customer: replied 6 months ago.
Alright bud I'm going to see if the Chevy house can Flash the eyes back to stock and I'll get back to u and let u know what happens, if they Caint do it tommorrow can I pull another ecm off another LB7 or are they vin locked???
Customer: replied 6 months ago.
Eyes "ECM" *****
Expert:  Chris (aka-Moose) replied 6 months ago.

The ECM is not vin locked but programming is required when swapping.

Expert:  Chris (aka-Moose) replied 6 months ago.

Hello again Chris here,

  1. I have to assume you were not pleased with my help, because you have not replied or rated the post.
  2. What would you like to do regarding your question now?
  3. Do you still need help? Please reply I want you to get equal to or more than what you paid for.
  4. This post is coming up on the 7 day mark where it times out. That can prevent me from being able to post answers to your replies.

Thanks Chris