Please understand the way i explain my problem cuz i'm a total noob so do not know the right terminologies

anyways.... Lately when the car is parked outside in the cold over night or for a long period of time and i start my car, the start up seems to be louder than usual. When i first experienced this i thought there was a laundmower or something being used on my block and out of curiosity i rev it a couple of time and from between 2 - 1 rmps, it goes down faster than from 3-2 rpms. when the loud noise is not there, the rmps go down at a constant rate.

is there something wrong with the car or is this normal?

thanks for the help

 

Unless you have an exhaust leak what you are running into is normal for these vehicles. If you listen to your TL carefully when started after the vehicle is completely cold, you will notice the exhaust tone is louder/deeper. From what I know there is a valve which allows the system when cold to stay open, its purpose is to heat up the cats faster. After a few seconds to a min (Depending on how cold it is) the valve shuts and the exhaust gets quiet again.

Suggestion is start up your TL and stand behind it for a min. or two.. Listen to the exhaust and see if what your experiencing is what I discribed.

 

Could be power steering pump: check PS fluid level.

Doubt it, but could be serpentine drive belt, pulley/s, belt tensioner...

 

I've never had a car NOT do that after being parked outside in the cold for a while. My dad's G35 does it and so does my TL.

 

Completely normal. The TL has a unique warm up strategy to aid in quick catalyst and 02 lightoff. It runs extremely high EGTs in the first few seconds which makes the noise as the fuel is actually burning in the exhaust.

Revs always come down quicker when it's cold.

 

mine does the samething in the morning when I cold started my car, at engine area gives you loud noise,and I feel not smoothy when I step on the gas pedal it gives you some weird noise too I knew it was not feeling normal but its okay when the car complete warmed up say like 15 mins of driving. Also, I feel my car(07-base TL) does not sound powerful when I key in starting it, I am awared of other TLs-base have much more powerful sound when they started. So I brought my car to the dealer yesterday stated above issues, I asked then to check my ps pump, heat shield noise, but they told me I need to do TB cleaning, oil enjector clearning so they stolen me $110 of doing this. they told me thats why you feel you have trouble to start your car and gas pedal is not smoothy etc. delayed acceleration on the high gear. I mean is that right? I will need try to start my car tomorrow morning see whats goin to happen. Any advices? appreciated

 

^The engine is cold and the oil pressure isn't at it's peak. It's normal for the car to be hesitant and such when it's not fully warmed up. You'll notice that as the engine becomes warmer, the RPMs will slowly go down.

I'm not sure what you mean when you say it doesn't sound powerful. It's a luxury car so the manufacturer is going to make sure the engine/exhaust doesn't blow your eardrums out. The only way you'll get it to sound throatier or louder is adding aftermarket parts such as an intake, exhaust, etc. If anything, the car should be louder during a cold start up and get quieter as you drive, not the other way around. What kind of sound did you get when you stepped on the gas? Was it a whine or a clunk?

Btw don't ever take your car to the dealership for something small like that. Take it to a independent mechanic shop and see what they say first.

 

thanks for your advices.

1. stepping on gas pedal does not smooth when I cold start the car driving frwd, as i stepped harder, engine sounds nosiey.

2. after I done the TB clearning and oil inj cleaning, I found out the RPM aim between 0 and 1 level even I idle the car, do you think is it normal after being clearned?

3. what I meant by sounds not powerful meaning the car sounds weak when i start it maybe I got clean my air intake portion? I am having 49k mile on my 07TL.

 

Every engine will be louder when cold. Clearances have opened up, all kinds of noises can be heard if you listen closely. There's nothing wrong with the car at all. Oil flow and pressure is just about instant, it's just the clearances and in the case of the first 10 seconds or so, it's the exhaust due to the warmup strategy.

Idle will always be higher when cold.

I'm assuming most people on here have never driven an older carbureted car when cold if you complain about the TL's cold manners.