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Hey guys,
When the car is at idle I'm hearing a loud hissing noise like there is a vacuum leak coming right from the manifold and I can't see a thing wrong with it, but I might just be missing something. Does anyone hear anything like that under their hood? Is it just normal? It sounds like more than just injectors and valves. Here is where the noise is coming from:
EDIT: This is a video I took. It sure sounds like a vacuum leak but is it possible that it's just the sound of air rushing through the piping? You can hear it plain as day in the video:
ive noticed that too i think normal.
i found nothing by spraying everything with starter fluid i think it's just
air rushing in the intake. there's a weird valve system in the intake i think that's making the sounds.
To Find the leak, You need to do Or have done what we call a "Smoke-Test" to Find the leak. The plastic intake these days is very deceptive thing However ,The Video Sounds like a leak. I recommend doing the smoke test here as it allows you to identify the leak as is sits, rather than just taking it apart in hopes to find Something or creating a bigger problem. Have you noted a Higher than normal idle, or any lean Codes..?
To Find the leak, You need to do Or have done what we call a "Smoke-Test" to Find the leak. The plastic intake these days is very deceptive thing However ,The Video Sounds like a leak. I recommend doing the smoke test here as it allows you to identify the leak as is sits, rather than just taking it apart in hopes to find Something or creating a bigger problem. Have you noted a Higher than normal idle, or any lean Codes..?
No, I havent really noticed any idle issues or codes. I have noticed a little bit of a whistle sometimes when i give it full throttle and the idle also dips very low and almost stalls for a second when I put the car in gear (automatic) when it's very cold outside right after I start it up.
I just replaced the upper intake manifold gasket when I replaced the valve cover gasket to see if it would help, because I heard that could cause problems. Nothing changed.
Also had some guys I know do a smoke test a while ago to try to find any leaks but they didn't find anything...might i add though that they work exclusively on BMW's although the fundamentals of an engine should basically be the same. I wasn't sure what part of the engine they hooked the smoke machine up to to check for leaks...
ive noticed that too i think normal.
i found nothing by spraying everything with starter fluid i think it's just
air rushing in the intake. there's a weird valve system in the intake i think that's making the sounds.
12-06-2021, 06:30 AM
