Dreaded P0505 FIXED
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Dreaded P0505 FIXED
Most posts list the problem and potential solutions but rarely do I see the confirmed fix! So, after pulling my hair out trying to figure out the P0505 I wanted to share how I finally fixed it. Symptoms other than the CEL were high/surging idle and bucking when on/off gas. I had sprayed carb spray on cold running motor to check for vacuum leaks-none. I foolishly bought an IAC valve (luckily only paid $50) The culprit was the f&%#,n PCV valve. Only use a Honda one, it made all the difference and the CEL finally went away.
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Re: Dreaded P0505 FIXED
OP.. How did you isolate the issue to the PCV valve? Testing or random part changing. Was it blocked (ball not rattling) or torn PCV hose or other?
I've used aftermarket PCV's without issue a few times. I'd prefer an OEM but they are more expensive and can be a longer wait if ordering from dealer or online.
I've used aftermarket PCV's without issue a few times. I'd prefer an OEM but they are more expensive and can be a longer wait if ordering from dealer or online.
If you think a good mechanic is expensive, try hiring a bad one
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I would think that symptoms would start as soon as the aftermarket part was installed.
A PCV valve not only has a job to do, it is also a calibrated vacuum leak. If the new part does not flow the same amount as the original, it effectively becomes an extra vacuum leak and it can throw off things like idle speed...and/or....fuel trims.
I guarantee you can pull all of your hair out trying to figure it out..you can't hear it....and it's sure not the first thing anyone usually thinks of as a cause.
Back in the days I was at a Mazda dealer, I used to run into issues with carbureted cars having lean idle conditions caused by PCV that flowed too much.
I have seen some Ford products set lean codes that were caused by a faulty PCV valve.
A PCV valve not only has a job to do, it is also a calibrated vacuum leak. If the new part does not flow the same amount as the original, it effectively becomes an extra vacuum leak and it can throw off things like idle speed...and/or....fuel trims.
I guarantee you can pull all of your hair out trying to figure it out..you can't hear it....and it's sure not the first thing anyone usually thinks of as a cause.
Back in the days I was at a Mazda dealer, I used to run into issues with carbureted cars having lean idle conditions caused by PCV that flowed too much.
I have seen some Ford products set lean codes that were caused by a faulty PCV valve.
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I would think that symptoms would start as soon as the aftermarket part was installed. A PCV valve not only has a job to do, it is also a calibrated vacuum leak. If the new part does not flow the same amount as the original, it effectively becomes an extra vacuum leak and it can throw off things like idle speed...and/or....fuel trims.
What's a carburetor?..lol
If you think a good mechanic is expensive, try hiring a bad one
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What's a carburetor?..lol
Back when I was in school, fuel injection was for Diesels, racing, and exotic cars.
For regular everyday cars fuel injection was just a passing fad. It would never catch on.
If I see something that old roll into the shop nowadays, I run and hide. I feel sick. I hear my mom calling.
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Last edited by Wankenstein; Nov 23, 2016 at 09:37 PM.
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If you think a good mechanic is expensive, try hiring a bad one
Joined: Dec 2011
Posts: 32,017
Likes: 256
From: Midwest. Aiming about mid-chest
Rep Power: 519 Re: Dreaded P0505 FIXED
I can make a water manometer if I have to, and I still have an old Uni-Syn in my toolbox:
