12 Valve 2nd Gen Dodge Cummins 94-98 Discussion of 12 Valve 5.9 Liter Dodge Cummins Diesels with P7100 Injection Pumps

New 12 valve light on power

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Old 04-01-2010, 09:07 AM
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Default New 12 valve light on power

I just bought my new truck off a guy in corsicana. Its got the big 215 pump in it with 191s and no fuel plate and the afc is turned up. When i drive the truck is smokes like a mobile forrest fire but it is really slow, through every gear it just bogs out no matter how high of rpms you get it to in the gear before. im gona put a # 6 plate in it today and turn the star wheel down today, but what else can i do to make it faster. I was thinking a turbo or maby bumping up the timing but not for sure thanks.
 

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Old 04-01-2010, 09:51 AM
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With all the mods you report on that truck, I'd have to say that it is probably set up to pull hard at WOT, but it will probably suck everywhere else in the rpm range.

I'd dial it back a bit and see if you can clean it up. Will probably drive better across the board, then add back in power mods so that they work together. More to this diesel stuff than just dumping fuel into the motor. Like all engines, it needs to be the right amount, at the right time, and under the right circumstances to make power instead of just excess fuel smoke.

One other thought -- how good is the transmission holding the power? Any indication that you are slipping?
 
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Old 04-01-2010, 10:18 AM
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your putting the fire out. your adding way to much fuel down low, and not enough turbo on the top end.
 
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Old 04-01-2010, 10:34 AM
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Originally Posted by 12valvecory
I just bought my new truck off a guy in corsicana. Its got the big 215 pump in it with 191s and no fuel plate and the afc is turned up. When i drive the truck is smokes like a mobile forrest fire but it is really slow, through every gear it just bogs out no matter how high of rpms you get it to in the gear before. im gona put a # 6 plate in it today and turn the star wheel down today, but what else can i do to make it faster. I was thinking a turbo or maby bumping up the timing but not for sure thanks.
How long have you had your diesel for? Because cummins SOUND like they are being lugged out at low rpms or when casually changing to the next gear and they sound VERY similar to tractors and big rigs. So keep in mind the exhaust note is very different on a cummins compared to other diesels.
 
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Old 04-01-2010, 10:50 AM
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those 191 fuel alot by adding that number 6 plate and tuning the afc you should help that truck tremendously
 
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Old 04-01-2010, 11:35 AM
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just got this truck but use to have a 94. The tranny is fine but just lugs out and doesnt make good boost.
 
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Old 04-01-2010, 11:53 AM
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have you checked for boost leaks? do you have a boost gauge? if so, whats the peak psi when it is spooled?
 
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Old 04-01-2010, 01:00 PM
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what you getting for boost? try tuning the afc donw and see if that helps
 
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Old 04-01-2010, 04:57 PM
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Ok so i went to put my #6 plate in the truck and pulled the AFC out and found that it was gutted so now im going to a local shop to try to put it back together i guess that was way it was lugging so bad all the time.
 
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Old 04-01-2010, 05:59 PM
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A gutted afc is basically direct fuel control with your right foot. It's actually very very effective with being fast this way but takes a LOT of skill to learn to drive like that.
 


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