Noise at Startup
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Joined: Jan 2016
Posts: 62
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From: Fort Walton Beach, Florida
Noise at Startup
Over the last couple of days when I start my car there is a noise that I can't determine the cause of. I know the sticky says that these cars sound like a sewing machine at startup from the valve train but this is much louder than a sewing machine. I also noticed the volt meter reads around 11-12 while the noise is going on but as soon as it stops the volt meter jumps up above 13. Could it be the alternator?
Also, the noise only occurs if the car has been sitting for a while and it's cold.
Thanks in advance for the help!
Also, the noise only occurs if the car has been sitting for a while and it's cold.
Thanks in advance for the help!
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That doesn't sound like valve train to me. Hard to say what it is but if your volt meter continues to have that jump in voltage, that might be a good place to start. I'd use a stethoscope and see if the noise is much louder when you put the stethoscope on the alternator housing vs putting elsewhere on the engine.
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From: San Diego Kalifornistan
Sounds like a really bad bearing in one of the pulleys. I'd take off the serp belts and check for noise/play/wobble in all the pulleys and idlers. I wouldn't expect a sound like that to magically disappear when the cars warms up though. Strange.
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That doesn't sound like valve train to me. Hard to say what it is but if your volt meter continues to have that jump in voltage, that might be a good place to start. I'd use a stethoscope and see if the noise is much louder when you put the stethoscope on the alternator housing vs putting elsewhere on the engine.
Hope you can trace it down and it is a fairly easy fix.
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Have you crawled underneath and looked/checked for anything obvious? Check for loose fasteners, panels, loose starter bolts, etc.........
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Something else came to mind and that is your A.I.R. pump. It mainly only operates on startup and the engine is in Open Loop mode, as the engine warms and the O² sensors heat up, it shuts off as the the engine goes to Closed Loop.
Left front, below the headlight area.
Left front, below the headlight area.
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Joined: Jan 2016
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From: Fort Walton Beach, Florida
Sorry all, since I work all week I haven't been able to troubleshoot the issue. I did create a video hoping that might help everyone visualize the problem.
Tomorrow I'll be popping the hood and trying to determine the cause. The most difficult part is the noise only lasts 2-4 minutes at startup and then I have to wait 3-4 hours without driving it to make the sound come back.
Thanks again for taking the time to help.
Tomorrow I'll be popping the hood and trying to determine the cause. The most difficult part is the noise only lasts 2-4 minutes at startup and then I have to wait 3-4 hours without driving it to make the sound come back.
Thanks again for taking the time to help.
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Joined: Jan 2016
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From: Fort Walton Beach, Florida
Thought today was going to be an easy relaxing day.
Plan was to remove the belts to eliminate cause of engine noise. While I was at it I replaced the plugs too. After removing the two belts and starting the car the noise was gone. So that narrowed it down. Put the belt to the air pump back on and started the car. There was that damn noise again. At least now I've narrowed it down. BUT, when I went to shut off the car the engine wouldn't shut down. No matter what I did it kept trying to run almost like dieseling but not quite. When I put the key back to start it would run normal again. So I turned the key to off, put it in 5th and shut it down that way BUT, the battery was boiling and I quickly grabbed the wrench to disconnect the negative and it was smoking finally got it disconnected from positive and negative terminals but the negative end was melted.
What the Hell???
Plan was to remove the belts to eliminate cause of engine noise. While I was at it I replaced the plugs too. After removing the two belts and starting the car the noise was gone. So that narrowed it down. Put the belt to the air pump back on and started the car. There was that damn noise again. At least now I've narrowed it down. BUT, when I went to shut off the car the engine wouldn't shut down. No matter what I did it kept trying to run almost like dieseling but not quite. When I put the key back to start it would run normal again. So I turned the key to off, put it in 5th and shut it down that way BUT, the battery was boiling and I quickly grabbed the wrench to disconnect the negative and it was smoking finally got it disconnected from positive and negative terminals but the negative end was melted.
What the Hell???
Thread Starter
Advanced
Joined: Jan 2016
Posts: 62
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From: Fort Walton Beach, Florida
Thought today was going to be an easy relaxing day.
Plan was to remove the belts to eliminate cause of engine noise. While I was at it I replaced the plugs too. After removing the two belts and starting the car the noise was gone. So that narrowed it down. Put the belt to the air pump back on and started the car. There was that damn noise again. At least now I've narrowed it down. BUT, when I went to shut off the car the engine wouldn't shut down. No matter what I did it kept trying to run almost like dieseling but not quite. When I put the key back to start it would run normal again. So I turned the key to off, put it in 5th and shut it down that way BUT, the battery was boiling and I quickly grabbed the wrench to disconnect the negative and it was smoking finally got it disconnected from positive and negative terminals but the negative end was melted.
What the Hell???
Plan was to remove the belts to eliminate cause of engine noise. While I was at it I replaced the plugs too. After removing the two belts and starting the car the noise was gone. So that narrowed it down. Put the belt to the air pump back on and started the car. There was that damn noise again. At least now I've narrowed it down. BUT, when I went to shut off the car the engine wouldn't shut down. No matter what I did it kept trying to run almost like dieseling but not quite. When I put the key back to start it would run normal again. So I turned the key to off, put it in 5th and shut it down that way BUT, the battery was boiling and I quickly grabbed the wrench to disconnect the negative and it was smoking finally got it disconnected from positive and negative terminals but the negative end was melted.
What the Hell???
1. Replace the melted negative cable
2. Have the battery tested
3. Reattach the alternator belt
My biggest concerns are why wouldn't the car shut off and when I got it to shut off why did the battery boil?
Thanks for your ideas!
Instructor
Joined: Aug 2015
Posts: 181
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From: San Diego Kalifornistan
When you say air pump, do you mean AC compressor?
I would get that battery tested first and fix the cable. If I understand correctly, you were running the car without the alternator belt, which would have put a heavier than normal load on your battery. I wouldn't think that this would make the battery boil, but if the battery was already weak or had some kind of internal issue, this may have tipped it over the breaking point. How old is the battery?
As far as the car continuing to run even with the key off, that one is beyond my understanding. If nothing else I'll bump this back to the top and hopefully someone with more knowledge than I can help.
I would get that battery tested first and fix the cable. If I understand correctly, you were running the car without the alternator belt, which would have put a heavier than normal load on your battery. I wouldn't think that this would make the battery boil, but if the battery was already weak or had some kind of internal issue, this may have tipped it over the breaking point. How old is the battery?
As far as the car continuing to run even with the key off, that one is beyond my understanding. If nothing else I'll bump this back to the top and hopefully someone with more knowledge than I can help.
Thread Starter
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Joined: Jan 2016
Posts: 62
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From: Fort Walton Beach, Florida
When you say air pump, do you mean AC compressor?
I would get that battery tested first and fix the cable. If I understand correctly, you were running the car without the alternator belt, which would have put a heavier than normal load on your battery. I wouldn't think that this would make the battery boil, but if the battery was already weak or had some kind of internal issue, this may have tipped it over the breaking point. How old is the battery?
As far as the car continuing to run even with the key off, that one is beyond my understanding. If nothing else I'll bump this back to the top and hopefully someone with more knowledge than I can help.
I would get that battery tested first and fix the cable. If I understand correctly, you were running the car without the alternator belt, which would have put a heavier than normal load on your battery. I wouldn't think that this would make the battery boil, but if the battery was already weak or had some kind of internal issue, this may have tipped it over the breaking point. How old is the battery?
As far as the car continuing to run even with the key off, that one is beyond my understanding. If nothing else I'll bump this back to the top and hopefully someone with more knowledge than I can help.
Your right it is the one that drives the AC. I'm wondering if only running one belt would have caused the engine not to shut off.
Last edited by Ronbo1786; Feb 21, 2016 at 04:40 PM.