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Loss Of Power Under Heavy Acceleration

TravisAZ

By TravisAZ
in Duramax Diesel & 8.1L Big Block

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TravisAZ Enthusiast

TravisAZ

Posted
Posted

Hey guys - posting this for a buddy.

 

He is experiencing a loss of power under heavy acceleration in his 2002 2500 with the DMax. Apparently the truck runs fine under normal conditions, but he has lost the acceleration he expects when he really gets into the pedal. I know he has had a couple of really dirty fuel filters - to the point that he changed gas stations and suspected they had really dirty tanks.

 

He has had it to a couple of mechanics without any really concrete diagnosis. The last guy told him "An injector pump might fix it" and quoted him 2k or so for the work.

 

Im not sure I am buying that. Would a faulty injector pump cause this? Any steps we could take to diagnose this ourselves?

  • 3 months later...
GMTRUCKS Enthusiast

GMTRUCKS

Posted
Posted
Hey guys - posting this for a buddy.

 

He is experiencing a loss of power under heavy acceleration in his 2002 2500 with the DMax. Apparently the truck runs fine under normal conditions, but he has lost the acceleration he expects when he really gets into the pedal. I know he has had a couple of really dirty fuel filters - to the point that he changed gas stations and suspected they had really dirty tanks.

 

He has had it to a couple of mechanics without any really concrete diagnosis. The last guy told him "An injector pump might fix it" and quoted him 2k or so for the work.

 

Im not sure I am buying that. Would a faulty injector pump cause this? Any steps we could take to diagnose this ourselves?

 

 

Tell him to check his air filter, because if thats the problem, under accelleration the engine isn't getting enough air, and is getting too much fuel. The only other thing i can think of is a partially clogged fuel filter, or bad fuel. I highly doubt its the injector pump, sounds to me that your mechanic just wants to make some extra cash, i have never heard of anybody having injector pump trouble in a D-max. I know a couple of guys with D-max's up here in maine that pull trailers and one of them has over 200k miles on the truck, and they have no trouble at all. Hope this helped good luck. - Brad

  • 4 weeks later...
planenut_2000 Enthusiast

planenut_2000

Posted
Posted

First thing he needs to have the fuel filter checked for excess vacuum under hard acel. If thats ok, then the fuel pump pressure should be ramped up with the tech 2 scanner to see if it achieves max pressure. If it fails to get max pressure, then your probably looking at replacing all the fuel injectors

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