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I'm experiencing low boost of 15 to 20 psi on FOT heavy

Customer Question
I'm experiencing low boost...

I'm experiencing low boost of 15 to 20 psi on FOT heavy loaded and speratic power loss..

Mechanic's Assistant: What's the make/model/year of your truck? Engine type?

05 kw w900l c15 acert twin turbo 475hp

Mechanic's Assistant: Are you fixing your truck yourself? What have you tried so far?

Recent issue

Mechanic's Assistant: Anything else you want the truck mechanic to know before I connect you?

No CEL has come in either

Submitted: 3 years ago.Category: Medium and Heavy Trucks
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Answered in 1 minute by:
5/31/2019
Technician: Cat Man, Cat Engine Expert replied 3 years ago
Cat Man
Cat Man, Cat Engine Expert
Category: Medium and Heavy Trucks
Satisfied Customers: 10,344
Experience: I am ASE Master Truck Certified.
Verified
Thanks for asking your question. I will try and help you out.Thanks for the information.Since the check engine light does not come on, I would suspect 1 of 2 things are causing your problem.The first is low fuel pressure. If there is a low fuel pressure problem, the check engine light will not come on and the engine will have low power. Your engine should maintain a fuel pressure between 75 and 90 psi. There is a plug beside of the secondary fuel filter that is used to check the pressure. If it is low, I would first try the fuel filters if you haven’t already. If it is still low, you may have a failed fuel pressure regulator, which is located underneath the bottom of the filter housing. I have replaced a ton of these for low fuel pressure. It is kinda a known problem. You could also have a weak fuel transfer pump or restricted hand primer pump, if your engine has one.Second I would suspect you have a low boost condition. This can be caused by a leak in the air piping or air to air aftercooler on the truck. I would first inspect all of the piping to see if there is a hole in any of the rubber boots that hold the pipes. From there you may want to cap off one side of the air to air cooler, and pressurize it. They have been known to crack and leak and cause low boost.Please let me know if you need more help or have more questions.
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