How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Daniel Wilson Your Own Question
Daniel Wilson
Daniel Wilson,
Category: Medium and Heavy Trucks
Satisfied Customers: 5446
Experience:  Owner at DJ Wilson
Type Your Medium and Heavy Trucks Question Here...
Daniel Wilson is online now
A new question is answered every 9 seconds

C7 will not start check fuel pressure at fuel filter at quick

Customer Question

c7 will not start check fuel pressure at fuel filter at quick connector barley moves 15 lbs gauge installed fuel pressure regulator same thing how much pressure should be at connector no matter what should be mechanical pump and have cranking pressure ????
Submitted: 1 year ago.
Category: Medium and Heavy Trucks
Expert:  Daniel Wilson replied 1 year ago.
Hi my name is***** will be glad to help. That is low pressure. If the regulator did not correct your problem and there are no leaks or restrictions it leads to a faulty transfer pump.
Expert:  Daniel Wilson replied 1 year ago.
Are you getting any fault codes? If so what are they? Your engine should maintain a fuel pressure between 65 and 85 psi. Usually low fuel pressure will throw a fault code.
Expert:  Daniel Wilson replied 1 year ago.
Plug or restrict the fuel return line and see if the pressure goes up and the engine starts. Let me know
Customer: replied 1 year ago.
dan sorry did not get back sooner truck broke down on road no fault codes i have cranking rpms with scanner i replaced fuel regulator will any thing else keep this from building pressure beside faulty pump
Expert:  Daniel Wilson replied 1 year ago.
If you have good fuel pressure then you also need 870 psi of injection actuation oil pressure and read at the sensor port for starting. Is the pressure is low cranking you could have a bad IAPR valve (Pressure regulator), Leaks in the high pressure rail/injectors, etc