Strange Noise On and Off Behind Dash? (now with video)
Strange Noise On and Off Behind Dash? (now with video) EDIT: Updated with video in post #13
This has only happened a about 3 times in the past few months. It sounds kind of like a winch operating if you've ever heard that, but a sort of electronic. Like a really loud fuel pump, slightly lower in tone and the noise is coming from up front. It is about as loud as a normal spoken voice. All the times it has happened I've been driving and could not pull over to listen to it, once I got near a place to pull over to listen, it stops. That's why the best I can pinpoint it is behind the dash because that's where it sounds like it's coming from. The first time this happened it started right after I pulled out of my parking space. It stopped whenever I touched the gas, then came back when I was off of it, regardless of speed or being at a complete stop. This only lasted about 1-2 minutes tops. The next few times it was the same, but didn't last as long, more likes 30 seconds or less. Obviously it's not very frequent, but it's not normal. Any ideas?
This is for my LS1
This has only happened a about 3 times in the past few months. It sounds kind of like a winch operating if you've ever heard that, but a sort of electronic. Like a really loud fuel pump, slightly lower in tone and the noise is coming from up front. It is about as loud as a normal spoken voice. All the times it has happened I've been driving and could not pull over to listen to it, once I got near a place to pull over to listen, it stops. That's why the best I can pinpoint it is behind the dash because that's where it sounds like it's coming from. The first time this happened it started right after I pulled out of my parking space. It stopped whenever I touched the gas, then came back when I was off of it, regardless of speed or being at a complete stop. This only lasted about 1-2 minutes tops. The next few times it was the same, but didn't last as long, more likes 30 seconds or less. Obviously it's not very frequent, but it's not normal. Any ideas?
This is for my LS1
Last edited by Marc3.4V6; Apr 28, 2013 at 04:40 PM.
On my 2001 Z28 (not the one in the sig) the wife says it sounds like a dremel tool on & off, I can't hear it myself. Does it alot according to her. Would love to know what it is.
I suppose a dremel tool at the lowest speed might sound like it, yes. It does have a circular sort of sound. Although this is loud enough that you would not mistake hearing it or not.
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This has only happened a about 3 times in the past few months. It sounds kind of like a winch operating if you've ever heard that, but a sort of electronic. Like a really loud fuel pump, slightly lower in tone and the noise is coming from up front. It is about as loud as a normal spoken voice. All the times it has happened I've been driving and could not pull over to listen to it, once I got near a place to pull over to listen, it stops. That's why the best I can pinpoint it is behind the dash because that's where it sounds like it's coming from. The first time this happened it started right after I pulled out of my parking space. It stopped whenever I touched the gas, then came back when I was off of it, regardless of speed or being at a complete stop. This only lasted about 1-2 minutes tops. The next few times it was the same, but didn't last as long, more likes 30 seconds or less. Obviously it's not very frequent, but it's not normal. Any ideas?
This is for my LS1
This is for my LS1
Have you considered taking your vehicle in for a dealer diagnosis? If you like, I could definitely help you locate one nearest you and also contact and set up an appointment for you. I would need some brief information from you that you could private message me such as your full name, address, zip code, VIN# and mileage. Here to help.
Reggie B.
Gm Customer Care
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I think you are hearing the air injection pump....the PCM turns it on at times to test the o2 sensors check the air injection system valves and to see if the cats are getting up to temp fast. At night you may notice the headlights dim a little at times as the air injection pump turns on.
If you can't get the pump turned on you can try 5 dollars and a box of candy.
If you can't get the pump turned on you can try 5 dollars and a box of candy.
No thank you GM customer service.
Interesting RockinWS6. My headlights do sometimes dim at night. I have heard what I thought was the A.I.R. pump turn on and then go off at startup (mostly cold start), but that noise is higher pitched and not as loud and more consistent. This noise sometimes is loud enough it sounds like it's in the cabin, but I doubt that. It's also only happened a few times.
Interesting RockinWS6. My headlights do sometimes dim at night. I have heard what I thought was the A.I.R. pump turn on and then go off at startup (mostly cold start), but that noise is higher pitched and not as loud and more consistent. This noise sometimes is loud enough it sounds like it's in the cabin, but I doubt that. It's also only happened a few times.
If you still have the factory radio they have a cooling fan in them that is actuated off of radio internal temp. If the fan is failing you could be hearing the fan dying.
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Yes I still have A/C. I don't use it much at all. It happened again today and I was able to pull over and pop the hood, but my stupid iphone took so long to get to video mode that it stopped right before it started recording, grrRRRRRRR...when it stopped it almost made an air-like noise like a turbo blow off valve only not as loud.
Yes I still have A/C. I don't use it much at all. It happened again today and I was able to pull over and pop the hood, but my stupid iphone took so long to get to video mode that it stopped right before it started recording, grrRRRRRRR...when it stopped it almost made an air-like noise like a turbo blow off valve only not as loud.
Finally got a video, at the end of it a weedwacker starts up, ignore that. Almost seems like the noise is from a pulley and revving it doesn't make it go away as I thought it did before.
So far this doesn't happen at cold starts. The cold start I hear the usual air pump noise that I've always heard that is way fainter, whereas this is louder. Seems to be warm and hot starts it occurs.
So far this doesn't happen at cold starts. The cold start I hear the usual air pump noise that I've always heard that is way fainter, whereas this is louder. Seems to be warm and hot starts it occurs.
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I think you are hearing the air injection pump....the PCM turns it on at times to test the o2 sensors check the air injection system valves and to see if the cats are getting up to temp fast. At night you may notice the headlights dim a little at times as the air injection pump turns on.
If you can't get the pump turned on you can try 5 dollars and a box of candy.
If you can't get the pump turned on you can try 5 dollars and a box of candy.
