Q: Check engine light P0304 will not go away amidst multiple attempts.

asked by on June 21, 2017

2008 Chevrolet Impala LS 3.5 V6 flex fuel Check engine code: P0304

Please help my horror story. I purchased my Impala 2 years ago, love my car. However, there has been a shadow in the form of a check engine light that I have always had. I purchased the car, the check engine light came on: P0304, multiple maintenance trips and multiple fixes over these two years.

  • changed spark plugs
  • Replaced catalytic converter
  • Switched to premium octane gas
  • Purchased new gas cap
  • Tried two different fuel injectors

No matter the attempt for resolution, It comes back with P0304. The car otherwise runs fine, but I'm tired of having the check engine light on, especially since it disables the automatic start feature on my key remote. Any ideas on where to go next?

My car has 130000 miles.
My car has an automatic transmission.

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