Code P0304

2004 KIA OPTIMA
168,000 MILES • 2.7L • V6 • 2WD • AUTOMATIC
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CELESTE1996
  • MEMBER
  • 1 POST
Car shakes really bad when in drive and reverse. Rpm's are constantly jumping and is worse when the AC is turned on. (My AC is broken too at the moment). All the lights flicker a little. I have changed the spark plug in cylinder number four twice. Also, the check engine light randomly turns on and a day or two later turns off, and so on and so fourth. What can I do to fix my problem?
Apr 7, 2018 at 11:41 AM
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ASEMASTER6371
  • ✓ASE Certified Mechanic
  • 52,796 POSTS
  • ASE Certified Mechanic
Good evening.

Some causes are:

1. plug you did this already.
2. coil or wires to the coil.
3. vacuum leak.
4. injector or wiring not allowing fuel into the cylinder.
5. compression low from internal engine issue.

Roy
Apr 7, 2018 at 5:49 PM
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