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Discussion Starter #1
Hi all

I can hear that I have a vacuum leak when I accelerate.

Any ideas on how to find it? Soapy water? Take out air box, MAF, intake hose and inspect?

Is there anyway to tell if its the VANOS seal?

Any help would be much appreciated.
 

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VANOS seals going bad is a given. That will not cause a vacuum noise. You should replace those eventually, anyway. The likeliest place for vacuum leaks are the intake boots. Just remove and inspect. A tear will not always be visible and usually is on the bottom boot connected to the throttle body and ICV. There may be other locations but 30 min and you can rule these out and move onto another part.
 

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VANOS seals going bad is a given. That will not cause a vacuum noise. You should replace those eventually, anyway. The likeliest place for vacuum leaks are the intake boots. Just remove and inspect. A tear will not always be visible and usually is on the bottom boot connected to the throttle body and ICV. There may be other locations but 30 min and you can rule these out and move onto another part.
+1


vacuum leaks are popular issues with these cars and rest assured you aren't the only one to have this issue. check out the stickies and do a search and you'll find all the information you'll need. moiz21 gave you a nice jump off point though.
 

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Discussion Starter #4 (Edited)
Thanks Moiz21 and Isteq I removed the upper intake hose and lower boot/elbow I have cleaned them up and inspected them very carefully and I cannot see any signs of cracks, wear or softness in fact now that they are clean they look brand new.

Any ideas of where to go now? I read in another post to look at the exhaust hose so I will do that. Would starting the car with the intake hoses off and seeing of the vacuum noise is still present be of any benefit or will that just suck a load of crap into my engine? Should I replace the intake boot or upper hose or both anyway?

Also what are your thoughts on spraying the MAF sensor with CRC MAF cleaner whilst I am there.

Thanks
Glenn
 

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Cleaning MAF

I've cleaned mine for good measure along the way and car still runs perfectly. Just be extra careful not to spray too close to the actual sensor point as this is very delicate and very expensive if you damage it.

To check for vacuum leaks, what happened to the idea of spraying starting fluid around suspected areas and noting idle speed changes?


Thanks Moiz21 and Isteq I removed the upper intake hose and lower boot/elbow I have cleaned them up and inspected them very carefully and I cannot see any signs of cracks, wear or softness in fact now that they are clean they look brand new.

Any ideas of where to go now? I read in another post to look at the exhaust hose so I will do that. Would starting the car with the intake hoses off and seeing of the vacuum noise is still present be of any benefit or will that just suck a load of crap into my engine? Should I replace the intake boot or upper hose or both anyway?

Also what are your thoughts on spraying the MAF sensor with CRC MAF cleaner whilst I am there.

Thanks
Glenn
 

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Thanks Moiz21 and Isteq I removed the upper intake hose and lower boot/elbow I have cleaned them up and inspected them very carefully and I cannot see any signs of cracks, wear or softness in fact now that they are clean they look brand new.

Any ideas of where to go now? I read in another post to look at the exhaust hose so I will do that. Would starting the car with the intake hoses off and seeing of the vacuum noise is still present be of any benefit or will that just suck a load of crap into my engine? Should I replace the intake boot or upper hose or both anyway?

Also what are your thoughts on spraying the MAF sensor with CRC MAF cleaner whilst I am there.

Thanks
Glenn
should have used a capital "L" instead of a lower case "l" for my sn :facepalm:

but anyways.....easiest and safest way would to do a smoke test. allows you to easily spot the leak without risking damage to your sensor. another culprit can also be the VCG (valve cover gasket)
 

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Discussion Starter #7
Sorry Lsteq (is it a q cause it could be a g)

Thanks all. Amazingly I reassembled the intake hoses today and I can't seem to hear the vacuum leak whistle anymore. So for now it does not seem to be causing any issues so I think I will leave it for now and see if my mechanic can do a smoke test next service.

Howie
 

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Hi all

I can hear that I have a vacuum leak when I accelerate.

Any ideas on how to find it? Soapy water? Take out air box, MAF, intake hose and inspect?

Is there anyway to tell if its the VANOS seal?

Any help would be much appreciated.
Try your vaccum lines! Behind manifold,disa.. Front of firewall follow the line coming from 2nd air pump w o2 sensors cable... My lines were all melted , nasty plastic rubber.. Autozone sold hoses!
 

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Sorry Lsteq (is it a q cause it could be a g)

Thanks all. Amazingly I reassembled the intake hoses today and I can't seem to hear the vacuum leak whistle anymore. So for now it does not seem to be causing any issues so I think I will leave it for now and see if my mechanic can do a smoke test next service.

Howie
its Lsteg - should have thought out my user name i suppose. at least your leak is gone though. it's possible that part of the intake was just loose and left a space for extra air to sneak through. keep an eye on it now that you know what to look for.
 
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