1997 GMC Yukon Q&A

1997 GMC Yukon Question: whats causing the p0306 code

replaced rotor cap plugs wires o2sensors mass airflow sensor and still getting code p0306 and it has a distributor and a throttle body, so what now -
Answer 1
Did you clear the code after repair? If so check compression and for a vacuum leak on or near # 6 cyl. Third cyl on pass. side. -
Answer 2
check the coil -
Comment 1
Only one coil for all cylinders. Should not set po306. -
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