2002 pontiac firebird v6 codes p0174 and p0430

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2002 pontiac firebird v6 codes p0174 and p0430

Unread post by guest » Sat Jun 15, 2019 9:28 pm

2002 pontiac firebird v6 has codes p0174 and p0430 service faul codes ive been having this problem for three years

 

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carriedi
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Re: 2002 pontiac firebird v6 codes p0174 and p0430

Unread post by carriedi » Mon Jun 17, 2019 12:59 am

your codes may be connected. You should look at your fuel trims and your oxygen sensors.

p0174 is the engine running lean and p0430 is the cat. having low efficiency.

Looking at your O2 sensors and your fuel trim should show your computer is adding excessive fuel to make the engine run normal out the exhaust. The MAF and/or the MAP sensors tell the computer what fuel should be normal to run the engine. It's part of the calibrations set in the computer. So, the computer sees the air flowing through the engine and feeds so much fuel to make it run. Metering the fuel. Then the computer looks at the O2 sensors to see if everything is burning correctly. The O2 sensor readings override the normal setting and the fuel trims change to fix the O2 sensor readings. In your case, adding fuel. Compare the O2 reading between bank one and bank two. Long and short trims.

things you have to verify are: are the O2 sensors working correctly? Is the air meters reading correctly? Is the fuel delivery correct? Like dirty injectors. Is there a vacuum leak messing with the air flow reading?

If this problem has been going for three years, there's a good chance that the Cat. code is correct. If you have an engine that the computer has been adding fuel for three years you could have prematurely worn the Cat. out.

How does the engine run? Is it running rough? Any problems while driving? Start normally when you first start up in the mornings? Does the engine have a miss?

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