I have a 1998 chevy silverado Z71. Recently two of my spark plug wires were cracked and the engine would mis fire and stumble when gased. I got the distributor cap and plugs and wires changed and now it runs fine. But today i was driving up a hill and it lacked power and began to shake and stumble when gased again. Any ideas what is going on?

possibly O2 sensor?

 

if the check engine lamp is flashing it means possible damage has/is occuring to the emissions system... I'd recommend taking it to a shop and have a scan tool put on it checking the O2 sensors to see if they are still switching, and check out all other systems.

 

REMEMBER THIS -> Turn on key only to accessories, put in neutral, push gas pedal 3 times, holding down on third. Turn off key..

HEHE

GL
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