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2009 chevy malibu has codes p0101, p0420, and p0300

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2009 chevy malibu has codes p0101, p0420, and p0300
Submitted: 8 months ago.Category: Chevy
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Answered in 2 minutes by:
9/21/2017
Chevy Mechanic: Gunvir Singh,
 replied 8 months ago
Gunvir Singh
Category: Chevy
Satisfied Customers: 2,013
Experience: Master Tech at Kennesaw Auto Tech
Verified

Hello, let me review your request. Please stand by.

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Chevy Mechanic: Gunvir Singh,
 replied 8 months ago

How long has the engine light been on for? Are you also noticing any engine performance issues?

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Customer reply replied 8 months ago
engine is not performing well at all. There is no acceleration.
Chevy Mechanic: Gunvir Singh,
 replied 8 months ago

Has any recent repairs or service been performed on the vehicle?

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Customer reply replied 8 months ago
no
Chevy Mechanic: Gunvir Singh,
 replied 8 months ago

The code p0101 is for a fault in the mass air flow sensor circuit. So need to start by checking for any loose/damaged vacuum hoses. If good visually look at the mass air flow sensor filament for any contamination or dirt on it. If no contamination then the mass air flow sensor will need replacement. Usually p0300 is for a random misfire which can be repaired by a tune up, faulty coil or fuel injector. But a faulty mass airflow sensor can also cause engine to misfire and trigger dtc p0300. So i will recommend to check the mass air flow before checking the p0300. P0420 is for a catalytic working under specifications and mostly caused by an exhaust leak or a faulty catalytic converter.

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Customer reply replied 8 months ago
ok let me try the maf sensor first. Thanks
Chevy Mechanic: Gunvir Singh,
 replied 8 months ago

You're welcome and good luck with your vehicle, And please don’t forget to rate my performance in the upper left corner otherwise i don’t get compensated. Thank you and have a blessed day.

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Customer reply replied 8 months ago
tried maf sensor. engine is still not performing well.
Chevy Mechanic: Gunvir Singh,
 replied 8 months ago

I'm not goig to be online today. I will opt out and let another expert assist you.

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Chevy Mechanic: Jerry Newton, Chevy Technician replied 8 months ago
Jerry Newton
Jerry Newton, Chevy Technician
Category: Chevy
Satisfied Customers: 5,633
Experience: ASE Master Technician, L1, Master GM Technician. Over 20 years of bumper to bumper GM experience.
Verified

If the engine is not accelerating well, it is likely that you have a restricted catalytic converter, and this restriction will cause P0101 and P0300 codes. I would address that problem first.

The way to test it is with an exhaust back pressure tester, you can borrow one of these at a local parts store, like Advance, Autozone, etc. at no charge. Can you do that?

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Chevy Mechanic: Jerry Newton, Chevy Technician replied 7 months ago

Did you get this worked out?

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Jerry Newton
Jerry Newton
Jerry Newton, Chevy Technician
Category: Chevy
Satisfied Customers: 5,633
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