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al_fol

Boost and fueling question???

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I am new to this forum and really enjoy the education from all the posts. Just tested my turbo system and found a decent boost leak in the hose from the turbo to the intercooler. Started hearing the hissing sound at about 10psi. Have had some power issues with this truck and i am hoping this is the problem. Would this boost leak essentially keep the truck from fueling as it should? When i am pulling my 5th wheel this truck is really a slug. If i am thinking correctly the sensors will not see boost and therefore will not call for fuel. The truck smokes very little when pulling anything and will give a little puff when I goose it in neutral. This is my first diesel so i am really green but i have learned a lot. Truck info should hopefully be in my signature.thanks!!!

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Welcome to the site!Yes, a boost leak of that magnitude will effect fueling. I would install boost/EGT gauges to ensure you are now boosting/fueling as you should be. Since you just bought the truck have you done thorough maintenance on it? Filters, fluids, etc. What kind of truck are you coming from, and did you tow the same load with it?Look on your valve cover for your HP rating, 235 or 250?

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I have had the truck about a year, and yes I have done the maintenance (I'm, as my wife puts it, very anal about maintenance). Oil, air, fuel, FW/sep, tranny fluids etc.. have all been serviced. The truck is an 250hp SO motor. I moved up to the diesel from a chevy 1500 with 350 and no the chevy never towed the 5th wheel. I plan on putting some guages in the truck as soon as life and bills allow me to. I am getting tired of my buddies running off and leaving me on hills and such and they are pulling basically the same camper. Do you have a good source for this hose? I hope this is the culprit for my power issues.

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Is your OEM hose ripped or was it loose?If you want more power you could keep an eye out for a Smarty Jr, load it on SW1 and your motor is now a HO with better timing, not any more fuel than a 305 HO pushed with the same turbo you have. But I bet if you fix that leak (sounds like you may still have it) and you will get some more power.

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I have not fixed it yet, but i plan on it in the next few days. The hose in question is the one from the turbo to the intercooler (2.75 x 7"). It had several small rips/tears along the hose. When i put about 10psi on the system the soapy water i had sprayed on started to bubble. it only takes about 30 seconds and all the pressure was gone. Hopefully i can find this hose locally and this will fix my problem.

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I have not fixed it yet, but i plan on it in the next few days. The hose in question is the one from the turbo to the intercooler (2.75 x 7"). It had several small rips/tears along the hose. When i put about 10psi on the system the soapy water i had sprayed on started to bubble. it only takes about 30 seconds and all the pressure was gone. Hopefully i can find this hose locally and this will fix my problem.

If you have something like a Parker Hydraulics they keep boots in stock, and lots of places to order them online. Personally I would not be driving, especially towing, with a boost leak an no EGT gauge. When my IC was leaking the ECM was still fully fueling and the only way I knew something was wrong was a huge spike in EGT's and a 3-4 psi boost drop. The difference here is that it wouldn't leak until I hit full boost, full fuel, and then bleed off. With your setup leaking from the get-go you probably aren't ever achieving full fueling, but your also not getting all the air you need for the fuel you are getting.
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If you have something like a Parker Hydraulics they keep boots in stock, and lots of places to order them online. Personally I would not be driving, especially towing, with a boost leak an no EGT gauge. When my IC was leaking the ECM was still fully fueling and the only way I knew something was wrong was a huge spike in EGT's and a 3-4 psi boost drop. The difference here is that it wouldn't leak until I hit full boost, full fuel, and then bleed off. With your setup leaking from the get-go you probably aren't ever achieving full fueling, but your also not getting all the air you need for the fuel you are getting.

This^^^^^^:thumb1:

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I want to personally thank everyone for their replies and comments so here it goes "Thank You!!". I will have to order the hose on line because it is not available locally. I have found several sources to choose from. I certainly hope this gets my trucks power back to where it should be. Would this leak cause the truck to lose a few MPG? Also my truck makes very little smoke would that be a symptom also. i have the airdog100 and it should be supplying the cp3 with more than enough fuel to go. I guess if the sensors are not sensing boost there is no need to fuel. My next move will be some guages and the B/W pressure sensor and solenoid for the tranny.

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Smoke is not good, in fact your leak must not be huge or it would be smoking. The AD will supply the CP3 with all the fuel it needs, but the ECM still controls the fueling, so the AD wont effect power unless you had a restriction from the old pump, or were tuned higher than the stock LP could handle. As for the AD make sure you only run a Baldwin BF1275 and Donaldson P551315 on it.

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Thank you for the filter numbers. What is a good air filter to run in my stock but home modded air box. I have read a few threads about the 4" pleated one but have not run across a brand/part number. Thanks again for your help! Once i get my boost system put back together, for testing purposes how much air pressure should I use and how long should it hold it?

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Stock Filter?? Mine is stock but only about 2" thick. I am only replacing the one hose for now. Wish i could afford to do them all, but............Kids need lunch money, plus i pressure checked them and they seem to be fine. So in a perfect world the boost system should hold the pressure until i release it??

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I have the intake side of the boost system plugged as well, so i guess it should hold indefinately then.

Please explain..........por favor?????:smart:

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Sorry, i should have made my self a little clearer. I removed the boot from the intake horn(drivers side) and plugged it as well. I am pressurizing from the turbo through the boost cooler and ending just short of the intake horn. Essentially i am just pressurizing the boost system. Does that make sense?

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