Electrolytic capacitors are known to leak & fail causing a wide variety of symptoms in EFI trucks up to 1993, but most commonly fuel pump running continuously at key-on with crank-no-start. Around '94, the capacitors used were a different type that don't exhibit this problem as often (yet). Fortunately, it's relatively cheap & easy to replace them at home with any
cheap soldering iron, some flux-core electrical solder, and the replacement capacitors (which can be bought in overpriced kits like
this or in bulk). Some paper towel or Q-tips and dilute alcohol may also be needed to clean up the leaking electrolyte.
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See also:
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