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Discussion Starter #1
my mpg were 15-17 with city and hiway. they started slowly going down over the winter. my lift pump and injector pump went out. replaced them and added adrenaline andi can only get 12.5 to 13.5 at best with adr on PL01 driving easy. could something have messed up injectors when pump broke. any ideas on what i can try.
 

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My Injection Pump went out on my truck a few months ago. Before it went out I got about 15 to 16 mpg. When I took it into the local cummins shop the put the new pump in and told me that they could pop test the injectors because alot of the time some of the metal from the pump would get stuck or go threw the injectors. So I put new 175 hp injectors in after they told me that and I get 18 to 20 mpg now. So it could be your injectors.

It cost me about a 100 dollars to have my injectors pop tested.
 

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Like he said, could be injectors. My friend had a GDP pump go through his cp3 and injectors.. killed everything. Another thing you might wanna check though is your water temp. Being an older truck the thermostat could have gone out. In winter it wont get hot, but it wont get warm enough to let the cylinders get good and hot like they like to. Other than that make sure you keep all your fluids up. Engine, transfer case, differential. Keep the fuel and air filter clean. Keep your tires at a high PSI. Try some fuel additive.
 

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Discussion Starter #4
i have noticed the temp gauge running on the low side thanks for the help. i am kinda new to this diesel stuff. i will change the t-stat and see if that helps. i will price injectors also.
 

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when you got your 175 hp injectors did you have to make any other mods?
 

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I already had the juice/additude, afe intake, and 4" exhaust, but the only other thing that I did have to do was relocate my lift pump back toward the tank closer and install a fuel pressure gauge. and i drove the truck from california to virginia pulling about 8,000 lbs and had no problem at all and got 16 to 17 mpg. I have a few other mods now but nothing to major yet.
 

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Discussion Starter #7
installed t-stat today temp gauge backup to dead center were it should be, it was at about 165-170 range we will see if this helps. waiting for a price on new injectors from farmboys diesel
 

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Yea thats a common problem on the 24valves, keep an eye on that temp. Just hope you didnt buy anything other than cummins thermostat cause it will not last...
 

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Discussion Starter #9
i bought a napa t-stat i will keep a eye on it and next time i will buy a cummins one thanks for the help
 
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