Rough idle, codes p0 171,174,300

2004 SUZUKI VERONA
174,550 MILES • 2.5L • 6 CYL • 2WD • AUTOMATIC
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#1SAINTSFAN
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i have changed the spark plugs,coils,PCV,cleaned the EGR. check the hoses and still getting rough idle. help please
Aug 10, 2019 at 7:44 AM
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KASEKENNY
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Hi,

The 0171 and 0174 are stating both banks are lean. The p0300 is a multicylinder misfire.

I attached a couple guides that will help with this.

https://www.2carpros.com/articles/repair-lean-mixture-codes-p0171-or-p0174-on-some-manufacturers

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

I suspect you have a vacuum leak that may not be a hose. Clearly this is something that is effecting the entire engine which is why both banks are lean. I would suggest taking the carburetor cleaner and spray it around the engine to see where the RPM goes up. More than likely it is an intake gasket leaking. Basically, you have unmetered air coming in somewhere causing it to go lean.

I attached the P0171 code. The P0174 is the same just for bank 2 so I didn't see the need to attach it.

Let me know what you find with this info and we can go from there. Thanks
Aug 11, 2019 at 9:16 AM
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#1SAINTSFAN
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thank you very much.
Aug 11, 2019 at 1:59 PM
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#1SAINTSFAN
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I have a new question I also have a 02 saab 9-5 2.3 areo and I changed my fuel pump and the reason I changed it cause my fuel gage would work sometimes then it would drop to empty can you help me do I have a reset the fuses are good and the relays help
Aug 11, 2019 at 3:03 PM
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RENEE L
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Hello,

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Renee
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Aug 11, 2019 at 6:05 PM