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mike switzer
mike switzer,
Category: Chevy
Satisfied Customers: 645
Experience:  lead diagnostic tech at Aamco
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Scanner reads 20% spark adv...seems high...random misfire

Customer Question

Scanner reads 20% spark adv...seems high...random misfire p0300..after replacing fuel pump..very strange ran fine before
JA: Have you ever replaced the fuel pump, or is this the original?
Customer: First time replace..pressure test 54 lbs..stays after shut off
JA: What is the model of your '54 Chevy?
Customer: Its 4.3 vortec..98 jimmy
JA: Are you fixing your Jimmy yourself? What have you tried so far?
Customer: Ohmed wires plugs cap rotor...ran fine fuel pump died..installed.. Now backfiring
JA: Anything else you want the mechanic to know before I connect you?
Customer: Nope
Submitted: 9 months ago.
Category: Chevy
Expert:  mike switzer replied 9 months ago.

before the fuel pump was anything else worked on?