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YOUR RESEARCHQuestion about the bellows tube and MAF
Leading reported evidence
Clean mass air flow sensor
Performed · outcome unconfirmed
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Performed · outcome unconfirmed · Original poster
The last time this happened I removed the MAF from the housing and cleaned it with alcohol.
Leading evidence: 'Clean mass air flow sensor' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Clean lasted me 8 months, til' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Suggestion · Original poster
Started the engine and let it run just for a few minutes, engine seems to idle just a bit higher but definitely smoother.
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Hi All,
The CEL just came on and my mechanic read the codes P1124 and P1126. He reset it and so far, only 4 miles actually, so good. The last time this happened I removed the MAF from the housing and cleaned it with alcohol. Let it dry and replaced. That cleaning lasted me 8 months, til today. So, I cleaned it again today and replaced. Started the engine and let it run just for a few minutes, engine seems to idle just a bit higher but definitely smoother.
Now the question:
I was researching here on the forum for other possible causes of the CEL and codes, and came across "bellows tube" several times. But no one explained what that is, and I didnt find a DIY for it.
Can anyone explain what the bellows tubes is/are? how many are there, what its function is and if there is DIY on it. I would love to tackle this project on my own, if possible.
I do have one other question. I recently noticed an increased level of noise in the car (passenger compartment) in gears 2-6 while the gas is applied. Sort of a hollow mechanical whirr (sorry cant explain any better) and it is not the sewing machine sound that is typical of the 996. I was wondering if when a bellows tube goes bad, does it make a sound like what I am hearing - this would help me diagnose better.
Thanx so much everyone,
Peter
It seems the bellows tube has been discussed plenty here but heres the synopsis. The air coming out of the case is vented into the air/oil seperator via a rubber "bellows" looking tube. Its only about two inches long. One side is clamped to the case and the other side to the oil seperator. Its located on the back side of bank two. Actually the best way to see it is to have the car in the air and look at the top portion of the engine on the drivers side, the bellows is plainly visible from this angle.
If the bellows did have a hole in it, the only thing you might hear is a small vacuum leak type noise.
On my old '99, I got the CEL at my 30k service, or right after, cost me a MAF replacement. Then it went off again.
Tech spent half a day diagnosing with the PST2 and reading codes, and then found a deteriorated bellows tube. It's an accordian style hose and takes about 20 minutes to replace, but it's in a bitch of a location to get to yourself. Part was about $25 I recall, but labor killed it.
Thanx, Is there any oil in it? I want to replace it at the same time I do my first DIY oil change. Oh and is there more than one (one per side of engine?)
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