code P0174 lean bank 2
05-29-2011, 11:39 PM
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code P0174 lean bank 2 what's causing my car to throw this code? ever since i cahnged my tall valve covers it's been throwing this code. everything seems to be pluged in correctly.
running tall valve covers with breather on oil cap neck,ls6 valley cover. any help would be apreciated. thanks.
running tall valve covers with breather on oil cap neck,ls6 valley cover. any help would be apreciated. thanks.
05-30-2011, 01:22 PM
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Did you check for cracked or loose/off vac hoses? if you are certin it's not a vac leak then i would also look at fuel pressure to make sure you have the proper line pressure at the rail. Restricted fuel supply will cause a car to run lean. If all checks out ok and have access to a scan tool observe HO2's and make sure they are fluctuating between 200 mV and 800 mV.
05-30-2011, 03:58 PM
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Are you also throwing a P0171? or just the P0174? Do you still have egr and A.I.R or blocked off? It's really hard to point you to the right direction without seeing what the PCM is seeing. I would suggest you find someone who has a good scan tool local that can see PIDS and record fuel trim data on both banks. I have one but im in OC about 1.5 hours away from you.
05-30-2011, 04:14 PM
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Are you also throwing a P0171? or just the P0174? Do you still have egr and A.I.R or blocked off? It's really hard to point you to the right direction without seeing what the PCM is seeing. I would suggest you find someone who has a good scan tool local that can see PIDS and record fuel trim data on both banks. I have one but im in OC about 1.5 hours away from you. If your only getting a P0174 that means bank 2 long term fuel trims are positve because the PCM is trying to compensate for a lean condition. If only bank 2 is the case look for burned HO2 wires, cracks on the exhaust near the H02's, and if you can observe the output signals from the HO2's with a scan tool.
Last edited by XpEdItIoUs; 05-31-2011 at 12:15 AM.
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05-30-2011, 08:33 PM
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sorry. It's running lean on bank 1 and bank 2 P0171 and p0174. I think it's the 02's that got burned out when i ran the car with a open Y for a month a few months ago. And I threw out the egr hoses. running a ls6 valley cover. what do you guys think?
05-31-2011, 12:03 AM
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Ok since it's lean on both banks I would check for vac leak and check your fuel pressure as well, if your fuel pressure is under at the rail from a clogged dirty fuel filter it will cause you to run lean as well. The possibility of the O2's getting contaminated and giving false reading from running open header is likely but I would rule out the common causes first.
05-31-2011, 12:19 AM
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It would be easier if you have a buddy with TECH 2, snap on modis, OTC Genisys or any good scanner that will let you look at PIDS. That way your not guessing.
