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Discussion Starter · #1 · (Edited)
I've replaced the O2 sensor, and put in new spark plugs. I've been looking for an air leak and found nothing. It still gets the CEL for "Too rich at idle, bank 1"

What else could be the problem? Is it possible that a broken PCV hose could cause this? I don't see how it could, I'm 99.999% sure that it has no connection to the idle. My top-of-the-engine PCV hose is broken in 2 pieces.

My revs sometimes have a spasm, and fluctuate for a couple seconds, then are normal again. I've tried just cleaning the MAF without removing it from the MAF housing.
 

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Are you still catless?
 

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Discussion Starter · #3 ·

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Discussion Starter · #5 ·
i got the same on my 2.4t when i mixed to much e85 with the normal gas.
how is your maf ?
I'm not sure, I really need to remove it completely and spray it down. Stupid ****ing FIVE POINT SECURITY screws. WTF Volvo?
 

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Yes it will... which means that yes, the broken pcv line could well be doing the dirty to you.

O2 sensors don't work by reading the 02 itself... so if you enter more air in after the meter (the maf) it thinks you are using not enough, and it thinks you are rich, when in reality, you are lean. Which is another reason to get the problem fixed.

I can't remember all the details right this minute (sorry, tired, long day and computer issues to boot, or rather, won't boot) but look it up, you'll see it's counter-intuitive, but true.
 

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Discussion Starter · #8 ·
Yes it will... which means that yes, the broken pcv line could well be doing the dirty to you.

O2 sensors don't work by reading the 02 itself... so if you enter more air in after the meter (the maf) it thinks you are using not enough, and it thinks you are rich, when in reality, you are lean. Which is another reason to get the problem fixed.

I can't remember all the details right this minute (sorry, tired, long day and computer issues to boot, or rather, won't boot) but look it up, you'll see it's counter-intuitive, but true.

How come a broken PCV line would cause that? It's not pressurized or anything.
 

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Did you check if I have a five-point bit? I didn't but will tomorrow. If you want, we can swap maf's and test it. I found my duct tape so we can tape the pipe to check it.
 

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How come a broken PCV line would cause that? It's not pressurized or anything.
The pcv comes back into the system post maf. If there is a hole in the pcv it is essentially an unmetered vac leak. If it's large enough that the car can no longer make accurate guesses on how much fuel to use, seeing that the maf is not useful at that point, it could set off the code you have.

Being that it's at idle, it's still a small leak, but it is probably less restrictive than the air filter/box, and the maf isn't being used until you overcome the restriction difference by getting on the gas.

That's my guess. :)
 

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Discussion Starter · #11 ·
The pcv comes back into the system post maf. If there is a hole in the pcv it is essentially an unmetered vac leak. If it's large enough that the car can no longer make accurate guesses on how much fuel to use, seeing that the maf is not useful at that point, it could set off the code you have.

Being that it's at idle, it's still a small leak, but it is probably less restrictive than the air filter/box, and the maf isn't being used until you overcome the restriction difference by getting on the gas.

That's my guess. :)
So you're saying, replace it because it needs to be replaced anyway and see if that fixes it?
 

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Discussion Starter · #12 ·
Did you check if I have a five-point bit? I didn't but will tomorrow. If you want, we can swap maf's and test it. I found my duct tape so we can tape the pipe to check it.
I thought I did. I'm pretty sure you don't, but check again. Swapping MAF's would definitely help pinpoint an issue! I should probably just replace the PCV lol
 

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If you don't have a 5-point security bit just switch out the whole MAF housing, it's easier to just loosen the clamps that hold it in place anyway :D

Also, just grind a + into them like I did to remove it, screw buying a whole set of bits for 1 problem :D
 

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So you're saying, replace it because it needs to be replaced anyway and see if that fixes it?
Since you looked for leaks and found nothing else, that's what I would do. Especially if it's easily taken care of with some heat shrink tubing to at least get you past your smog.
 

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Discussion Starter · #15 ·
Since you looked for leaks and found nothing else, that's what I would do. Especially if it's easily taken care of with some heat shrink tubing to at least get you past your smog.
Didn't think of that. That's not a bad idea. I'll probably do that, rather than remove the intake manifold and all that jazz.

If you don't have a 5-point security bit just switch out the whole MAF housing, it's easier to just loosen the clamps that hold it in place anyway :D

Also, just grind a + into them like I did to remove it, screw buying a whole set of bits for 1 problem :D
Yeah, I thought about that, and just replacing them with normal screws and/or bolts. So dumb..
 

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Yeah, I thought about that, and just replacing them with normal screws and/or bolts. So dumb..
Right? Like is there a huge gang out in the streets stealing just MAF sensors and selling them on the black market? :D



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Discussion Starter · #17 ·
Right? Like is there a huge gang out in the streets stealing just MAF sensors and selling them on the black market? :D



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I was over at firestone getting an alignment, and a guy pulled in because someone straight up just cut his cat out from under his car with a sawzall.
 

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I was over at firestone getting an alignment, and a guy pulled in because someone straight up just cut his cat out from under his car with a sawzall.
Happened to my truck when it was in the shop after my accident. They stole my radio, busted out all my windows and stole the cat. Needless to say they totaled it :(


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Glad I dont have a CAT for anyone to steal!
 

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Discussion Starter · #20 · (Edited)
Happened to my truck when it was in the shop after my accident. They stole my radio, busted out all my windows and stole the cat. Needless to say they totaled it :(


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Dude that just blows.



In other news:

I replaced PCV today, however AFTER doing so there's a nice loud HISS. I did NOT replace the intake manifold gasket, I decided to inspect it and see if it -had- to be replaced first. The issue is, I can't even fathom where it's coming from. It's coming from under the intake manifold for sure, and I'm 99.99999% sure it's not the inlet piping that connects to the TB. I couldn't find anything else, it's definitely coming from that general vicinity though. What else is there that I might have missed? Could I have cracked one of the PCV lines: i.e. the stupid ****ing hose that is actually bolted to the manifold via a banjo bolt?

The CEL hasn't returned yet, but the emissions stuff still aren't "ready" - The only thing is that there's still no pending code after a solid 30 minutes of driving.

My long term fuel trim is -1.56%
 
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