POST 1 / ORIGINAL POSTEROriginal post
Do you know what would be the source of a whooo sound I hear for a short period after the motor is started (cold)? Thank you. Regards,
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Do you know could be a whooo sound for a short period after the motor is started (col
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YOUR RESEARCHDo you know could be a whooo sound for a short period after the motor is started (col
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17 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
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POST 2Original post
Secondary air system pump perhaps? How long does it last?
POST 3Original post
Whoo hoo I get to go for a ride in my 996?
POST 4 / ORIGINAL POSTEROriginal post
Not long but it goes whoooo (deep tone whoo) when starts from cold. If I put it in reverse back out and lightly accelerate the throttle it has barely perceptible flat spot. If give it few more seconds before move it it is not there i guess. Thanks guys. Going off line to the track at Daytona. You guys coming down to speed week gigs? Regards,
POST 5Original post
It's the engine compartment fan. I noticed that mine has been doing the same thing- shouldn't it be coming on when it's HOT, and not cold? Mine only comes on when it's cold. Did some wires get reveresed or something somewhere in its maintenance life, or is it supposed to do this?
POST 6Original post
I've got the same sound, I thought it was a pump of some sort...
POST 7Original post
That's only in the mo'nin'. Bubb Rubb http://youtube.com/watch?v=Ac8-YVYlehg
POST 8Original post
Metal rubbing against metal prior to the Mobil 0/40wt making its merry way to the engine? Tom L 2002 C2
POST 9Original post
Its the, "WOW I have enough oil left in me to start this morning. AND I actually started" sound
POST 10 / ORIGINAL POSTEROriginal post
When she cranks up cold it makes a noise that is audible and never heard except for 30 seconds after started cold.
POST 11Original post
Secondary air system pump for sure - only happens during cold start. Secondary air system injects extra O2 into the exhaust system at cold start to give a cleaner burn and lower emissions. It's normal during colder weather.
POST 12Original post
This is purely a guess. Since the oil is cold and is not as viscous some parts of the engine actually gets hot faster then when the entire engine is at the normal temperature hence the fan/air pump is turning on.
POST 13Original post
as cdodkin stated its the secondary air pump turing on, it shoots extra air (hence the term air injection) into the exhuast to get the cats up to temperature as quickly as possible for emmissions reasons
POST 14Original post
SIA
POST 15Original post
sai.................I love that sound! Like the batmobile! Holy frostbite batman!
POST 16 / ORIGINAL POSTEROriginal post
Isnt it a problem if too loud?
POST 17Original post
ive never seen one that was too loud
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