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Discussion Starter #1
What’s going on guys just picked up another third gen! 07 5.9 mega cab 4wd fully loaded marine has 250k bought it from a family member who did meticulous maintenance at a well know diesel shop in there area. Well being as the mileage is about Tim injectors wear out and I don’t know if they have been replaced I searched for tests to do. I’m not getting any white smoke or lope even after the truck sat for 4 months literally 0 smoke. Also I’m not gaining oil level. But when I free rev the truck in idle the rpm sticks for 2-3 secs then drops down. I’ve been getting a ton of mixed information reading forums from people saying it’s programmed into the computer to do that and others guaranteed that that’s bad injectors. I’m just trying to prevent myself from sticking an injector and melting a cylinder as this truck has 0 blowby not even a haze TIA!
 

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As long as it's not hard starting, sounds like the injectors are fine. They may go another 50,000 miles before they start to go bad. If you start to see signs of them going bad, run a heavy dose of cleaner and lubricant to see if it fixes the issue. I have also read that RPMs hanging when you rev the engine is a sign of bad injectors. But, I have also read otherwise. When you rev the engine the RP goes up. That RP won't instantly diminish when you let off the throttle. So since that RP needs to be released, the RPMs will hang for a second until the RP drops back down.
 

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Reving up and slowing coming down is normal. If it actually hangs at a certain rpm for 2-3 seconds then thats an issue. If it comes down choppy, that's injectors.
 

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That is a correct statement on the rail presure and on the other hand these common rail engines do not like to be free revved so to speak
 

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IMO, At high miles/hours, each injector firing 3 times per each revolution, Injectors really become a maintenance item, especially with OEM filtration.
 

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Discussion Starter #6
Ya I’m kind of just leaning towards biting the bullet and buying a new set I just can’t bring myself to pay 3500 for a good set of 60-75 overs and I know I’ll hate myself even more if I put stocks back in 😂
 

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All I can say is, the 50hp injectors the PO to me put in, were definitely going bad and also did that rev hang nonsense.

I replaced them with BBI stage 1s and they rev up and drop like a rock.

I can say I noticed it while driving as well, have an auto truck. When WOT and I'd let off the pedal with the old set, the truck would keep accelerating for maybe a second or so.

With the new set, soon as I let off the pedal the truck stops accelerating immediately.
 
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All I can say is, the 50hp injectors the PO to me put in, were definitely going bad and also did that rev hang nonsense.

I replaced them with BBI stage 1s and they rev up and drop like a rock.

I can say I noticed it while driving as well, have an auto truck. When WOT and I'd let off the pedal with the old set, the truck would keep accelerating for maybe a second or so.

With the new set, soon as I let off the pedal the truck stops accelerating immediately.
The RPMs hanging for a second might just mean that the injectors have some wear, but aren't necessarily bad. But I'm far from an expert.
 
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The RPMs hanging for a second might just mean that the injectors have some wear, but aren't necessarily bad. But I'm far from an expert.
That wasn't my only symptom, just to be clear. It was one of a couple.

Do think it's sign to keep an eye on them though.
 
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Discussion Starter #10
I have very similar feeling after WOT pulls it would keep going for a second after. I mainly was worried about sticking an injector open as long as I’m not as risk of that I feel safer driving
 

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