2007.5 silverado 2500 with multiple codes

Toutle Duramax

New member
Dec 10, 2022
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Not sure what to do. dont want to just throw money at it. I have a 2007.5 silverado with 6.6 LMM it has 1000000 miles on it.Started running rough so It was about filter time so replaced filter. seemed to make it worse. So ordered hole new filter & housing with fuel lines. still no help. changed regulator & pressure plug. still no help. Took it to shop to scan in limp mode. This was results . Found multiple codes (po102, po118, po672, po676, po513, po0090 andp0087. We cleared them and currently only got P0672 AND P0676 Glow plugs. the fuel pressure will only build to 2/3 of the commanded pressure. Injection pump is weak. should I replace pump or what? does not have but 100 k, do they go bad that soon?

 
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2004LB7

Well-known member
Dec 15, 2010
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Norcal
with that many codes from multiple systems I'd think you got a bad ground.

I would not worry about the glow plug codes until you get the engine running good

for fuel pressure, you need to run a return rate test on all the injectors, the cp3 and the pressure relief. don't just throw parts at it.
 

Randy Horner

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Sep 26, 2022
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with that many codes from multiple systems I'd think you got a bad ground.

I would not worry about the glow plug codes until you get the engine running good

for fuel pressure, you need to run a return rate test on all the injectors, the cp3 and the pressure relief. don't just throw parts at it.
ok thank you for the reply. I will get a test kit and let you know results
 

08lmm72mm

Active member
May 13, 2019
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Saskatchewan, Canada
P0672 and P0676 are glow plugs #2 and #6 change them out they are cheap and easy to do. If you live in cold climate it will make your truck run rough with 2 bad ones. P0087 is low fuel pressure I'd do a bottle test on the FPRV to check it and it it leaks just put a race valve in for $30, it could also be pump or injectors but starting the bottle test is the cheap and easiest to start with. P0118 sounds like the ECT sensor might have the wires rubbed through somewhere it's right beside the alternator on the right. P0513 is the anti theft system, bad or weak batteries can set that one off, test your batteries.
 
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