I would start by checking the fuel pressure as this is the most common reason for a code 300. low fuel pressure will not provide enough fuel to the injectors for proper fuel mapping.
Would a vacuum leak do that too? Also, how to you swap the fuel pressure?
Dec 26, 2018 at 10:20 PM
ASEMASTER6371
✓ASE Certified Mechanic
52,796 POSTS
It is part of the pump.
you replace the fuel pump assembly.
no, a vacuum leak will not effect fuel pressure.
Roy
Dec 27, 2018 at 3:38 AM
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