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Replaced both 02 sensor on secondary exhaust 8 coil packs…

Replaced both 02 sensor...

Replaced both 02 sensor on secondary exhaust 8 coil packs spark plus ,mass air flow sensor spark plug wires ,purge valve and i still have code 300 and 138 will show up every now and then runs very rough

Mechanic's Assistant: Does the engine stall right after starting? And what about hesitation or jerking during acceleration?

Has to warm up if step down hard on it goes away then runs rough also on easy driving

Mechanic's Assistant: What year is your 300?

2003 6liter

Mechanic's Assistant: Are you fixing your 300 yourself? What have you tried so far?

Yes

Mechanic's Assistant: Anything else you want the mechanic to know before I connect you?

Just what i am missing i am a truck driver that can fix a big truck but getting very puzzled

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Answered in 2 minutes by:
11/19/2017
Roy
Roy, import/domestic specialest
Category: Chevy
Satisfied Customers: 7,728
Experience: ASE master tech for 40 years
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hello, my name is ***** ***** I will be glad to assist you. please allow me a couple of minutes to gather some basic info.

Roy

Ask Your Own Chevy Question

ok

the 300 code is a good indicator of low fuel pressure. have you checked the fuel pressure???

also, with the rough running, did you do a compression test when the plugs were out??

Roy

Roy
Roy, import/domestic specialest
Category: Chevy
Satisfied Customers: 7,728
Experience: ASE master tech for 40 years
Verified
Roy and 87 other Chevy Specialists are ready to help you
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Customer reply replied 7 months ago
compression ok fuel no plugs new
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