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Engine shutting off code spn 94 low fiel pressure. It shuts…

Engine shutting off code...

Engine shutting off code spn 94 low fiel pressure

Mechanic's Assistant: How long have you been experiencing power issues? Does the power come back on eventually?

It shuts off i wait 1minute fires up i go to move truck half blocock she will start sputtering fuel pressure drops i have laptop jpro hooked up

Mechanic's Assistant: Can you confirm the year of your Truck?

2012 mack pinnacle mp8

Mechanic's Assistant: The Mechanic will know how to help. Anything else you want them to know before I connect you?

I dont think so

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Answered in 7 hours by:
9/18/2020
Technician: Daniel Wilson,
 replied 1 year ago
Daniel Wilson
Category: Medium and Heavy Trucks
Satisfied Customers: 14,646
Experience: Owner at DJ Wilson
Verified

Hi my name is***** will be glad to try to help you out. Be sure to check for any leaks or restrictions between the fuel tank and fuel pump. Replace your fuel filter and empty your existing fuel filter into a clear container to look for any type of contamination of the fuel. If all of this checks out okay, low fuel pressure could potentially be caused by a faulty pressure regulator. Install a clear hose or site glass on the suction side as well as the return side to monitor for aeration of the fuel as there should be little to no air bubbles on both the supply or the return. If there are no problems found with actual fuel pressure or aeration of the fuel, it is possible you could have a problem with the fuel pressure sensor itself giving false readings. They recommend doing an injector test as well to confirm whether or not your injectors will pass an injector test with the appropriate diagnostic software. Reply back with the results of these checks if any further help is needed. Click on the link below for the fuel flow diagram to use as reference. It's a pleasure to help anyway I can.

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Customer reply replied 1 year ago
What I noticed looking into fuel tank when starting truck quite a few bubbles come out of return tube for a few seconds then they go away
Technician: Daniel Wilson,
 replied 1 year ago
Sight unseen it's hard to say whether or not it is of concern but you can always put a clear hose or sight glass in line for a more accurate assessment on the return and supply.
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Customer reply replied 1 year ago
Thank you please stop
Technician: Daniel Wilson,
 replied 1 year ago
You're very welcome it's been a pleasure. Please reach out to the website for any website concerns or billing concerns as professionals or users of the site like yourself and do not have access to any of that information.
Ask Your Own Medium and Heavy Trucks Question
Customer reply replied 1 year ago
Thank you please stop
Technician: Daniel Wilson,
 replied 1 year ago
I have to reply back to your replies so please don't respond back to my reply. Enjoy the rest of your weekend.
Daniel Wilson
Category: Medium and Heavy Trucks
Satisfied Customers: 14,646
Experience: Owner at DJ Wilson
Verified
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Daniel Wilson
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Daniel Wilson
Category: Medium and Heavy Trucks
Satisfied Customers: 14,646
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