Booming Sound On Start Up. Any Ideas?
#1
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I have a base 2007 911 with 19,700 miles and I noticed a few days ago upon start up-a booming thunder-like sound coming from up front. Nothing on the dash indicates anything is wrong-the car rides fine and the noise disappears after a minute or so. The car is under CPO warranty. It happens now every time I start the car.
Any ideas as to what may be causing this noise? It is definitely not a normal sound for my car.
Any ideas as to what may be causing this noise? It is definitely not a normal sound for my car.
#4
Race Director
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I have a base 2007 911 with 19,700 miles and I noticed a few days ago upon start up-a booming thunder-like sound coming from up front. Nothing on the dash indicates anything is wrong-the car rides fine and the noise disappears after a minute or so. The car is under CPO warranty. It happens now every time I start the car.
Any ideas as to what may be causing this noise? It is definitely not a normal sound for my car.
Any ideas as to what may be causing this noise? It is definitely not a normal sound for my car.
Even if they do not run all the time if the A/C is on when you start the engine the fans will come on.
If the fans are on all the time (even at low speed) or if the A/C is on when you start the engine then a radiator fan motor's bearings could be going out.
Also, check the power steering fluid level. The noise might be air in the system due to low fluid level which of course is due to a leak and the noise is this air (with some fluid) being circulated through the steering rack.
Hard to believe the noise could arise from air in the cooling system at least upon cold start since the coolant is blocked from flowing through the radiators by the closed thermostat. But check the coolant level -- with the engine cold -- just to be sure.
Long shot but another source of noise at the right front of the car is the vapor recovery/tank ventilation system and the noise might be a noisy valve or even a hose vibrating.
You need to be at teh front the car when the noise first appears and continues to more closely id the point from which the noise is coming from. Knowing this helps eliminate some possible causes and makes other causes more plausible.
Sincerely,
Macster.
#5
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Not sure if the radiator fans operate 100% of the time with the 997 models or whether they only come on when coolant temp climbs too high like with the previous models.
Even if they do not run all the time if the A/C is on when you start the engine the fans will come on.
If the fans are on all the time (even at low speed) or if the A/C is on when you start the engine then a radiator fan motor's bearings could be going out.
Also, check the power steering fluid level. The noise might be air in the system due to low fluid level which of course is due to a leak and the noise is this air (with some fluid) being circulated through the steering rack.
Hard to believe the noise could arise from air in the cooling system at least upon cold start since the coolant is blocked from flowing through the radiators by the closed thermostat. But check the coolant level -- with the engine cold -- just to be sure.
Long shot but another source of noise at the right front of the car is the vapor recovery/tank ventilation system and the noise might be a noisy valve or even a hose vibrating.
You need to be at teh front the car when the noise first appears and continues to more closely id the point from which the noise is coming from. Knowing this helps eliminate some possible causes and makes other causes more plausible.
Sincerely,
Macster.
Even if they do not run all the time if the A/C is on when you start the engine the fans will come on.
If the fans are on all the time (even at low speed) or if the A/C is on when you start the engine then a radiator fan motor's bearings could be going out.
Also, check the power steering fluid level. The noise might be air in the system due to low fluid level which of course is due to a leak and the noise is this air (with some fluid) being circulated through the steering rack.
Hard to believe the noise could arise from air in the cooling system at least upon cold start since the coolant is blocked from flowing through the radiators by the closed thermostat. But check the coolant level -- with the engine cold -- just to be sure.
Long shot but another source of noise at the right front of the car is the vapor recovery/tank ventilation system and the noise might be a noisy valve or even a hose vibrating.
You need to be at teh front the car when the noise first appears and continues to more closely id the point from which the noise is coming from. Knowing this helps eliminate some possible causes and makes other causes more plausible.
Sincerely,
Macster.
#6
Rennlist Member
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second that - people rarely check level of pentosin in the extension tank, and it may be the reason. but do not overfill it! as soon as you able to see some of it on the bottom of the tank - stop adding it. cap stick has to be wet only on its very end.
#7
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Okay. I isolated the source of the problem: the boom is coming from the left door-specifically the forward most big radio speaker just in front of the memory seat switches. Looks like the speaker is shot. That's one scary noise!
Any idea how much it will cost me to replace it? Non-warranty of course-still better than having something mechanically wrong with the car.
Any idea how much it will cost me to replace it? Non-warranty of course-still better than having something mechanically wrong with the car.
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#8
Race Director
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Okay. I isolated the source of the problem: the boom is coming from the left door-specifically the forward most big radio speaker just in front of the memory seat switches. Looks like the speaker is shot. That's one scary noise!
Any idea how much it will cost me to replace it? Non-warranty of course-still better than having something mechanically wrong with the car.
Any idea how much it will cost me to replace it? Non-warranty of course-still better than having something mechanically wrong with the car.
Roughly the labor required would be on the order of how long it takes to tear into a door to replace a bad window switch or door lock or something similar. Call it 2 hours or less.
Parts... Could be a couple of hundred dollars.
Thus I would guess you could get the car in and out and fixed for $500 or less.
Sincerely,
Macster.
#10
#11
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Never even considered the speakers. Of all the things that could account for the noise though that's the cheapest to address.
Roughly the labor required would be on the order of how long it takes to tear into a door to replace a bad window switch or door lock or something similar. Call it 2 hours or less.
Parts... Could be a couple of hundred dollars.
Thus I would guess you could get the car in and out and fixed for $500 or less.
Sincerely,
Macster.
Roughly the labor required would be on the order of how long it takes to tear into a door to replace a bad window switch or door lock or something similar. Call it 2 hours or less.
Parts... Could be a couple of hundred dollars.
Thus I would guess you could get the car in and out and fixed for $500 or less.
Sincerely,
Macster.
Anyhow, I contacted my dealer and he said this could be covered under warranty-I have CPO coverage. He mentioned there might be a "recall". I'm not getting my hopes up-I'm sure I will have to pay.
#14
Rennlist Member
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actually yes - i had same thing to my old amp when it died i got all speakers making low freq ramble but it was constant. it is very easy to check - just unplug your amp completely and see if ramble will be gone.