Cold Start/Noise
Asked by Ben Dec 22, 2008 at 12:17 AM about the 2004 Volkswagen Jetta GLS 1.8T Sedan FWD
Question type: Maintenance & Repair
When the car is started after sitting over night or after sitting out in the cold for a short time it makes a funny noise. Almost like there is something caught in the fan. But the noise changes with the RPM of the motor. But it goes away after about 2 minutes and I cannot figure it out. ANY IDEAS
8 Answers
I have a 2004 GLI. My car does the exact same thing every time i start it. it revs high and make s a noise. i let it run for about a minute and then it drops back down. ?
secondary air injection it draws exhaust gasses back into motor to make it warm up faster
Sounds like tappets. Once the oil gets thinned out(warm) and makes its way fully round the engine the noise will go like you say. Check oil level.
Your car Is equipped with a secondary air injection system,this system puts an air charge into the exhaust stream to get additional flow to the catalytic converter allowing it to get up to temperature faster and to bring the O2 sensors on line quicker,it all has to do with cold start up emission control,the fan motor may be on it's way out and that is what you are hearing ,some of the sound like a siren or a jet turbine when the get real bad,they will usually only cycle maybe one or two times then they are done until the next cold start cycle
Is there a fuse for the fan, if so where is the fuse??
In my case the noise is on start up. sounds like a fan but it is not ( disconnected the fan still makes the noise) The noise will happen when I shift to reverse or first also. It lasts about 15 seconds. It also will be noisy when I hit the recirculating mode on air conditioning.
Avidskier, did you ever get an answer? I have the same issue, and the description is spot on.
