I have only about 500 miles on my '06 TL so far, so maybe it will smooth out, but is a buzzy, roughish idle common to the TL? I mean, it sometimes makes the whole cabin vibrate when at a stoplight, or when sitting in my driveway.

I've had several V-6's (there 3 of them in my garage right now) and I haven't had this phenomenon before.

Is this considered "normal" for the TL, or can I expect it to smooth out over time?

 

That doesn't sound right to me. I have had three V-6s (Ford, Saab, and TL), and the TL is the smoothest quietest one of the bunch. In fact, it is almost as smooth as the 1989 Toyota Cressida I-6 I had, which ran like a Swiss watch.

 

I would say that its not normal...

Is this with the A/C off. Foot off the brake?

If I push on the break really hard I can make the RPMs drop a little, same for when the A/C kicks on. But normally its really smooth.

Use Shell Gas. Exxon sucks ass.

 

Hey, it's summer and I'm in Texas. 101 degrees. Hell yes, the A/C is on. LOL.

It does the buzzy idle at startup, then when I stop at a light or whatever, it vibrates some more. Kinda resonates around the cabin like bass on the sound system.

But the ones I test drove (including one they gave me for the weekend) did the same thing. I thought maybe it was something about the low miles, and when the engine got bedded in it would smooth out. My Lexus IS350 is so smooth and quiet at idle you sometimes can't tell if it's running. But it's a Lexus ...

 

Mike,

IMHO, the 2004-2006 TL does have an initially rough cold start idle. I believe Acura has tuned the engine to run as lean as possible to achieve its ULEV rating. My 05 TL now has about 5000 miles on it and it seems to idle much more smoothly than when it was new. It still feels a little rough each morning when the engine is cold, but I've become accustomed to it.

Hope this helps!

 

Thanks, Ogiewon. I kinda suspected it may have to do with the emissions control system, but I just haven't experienced that before in a Japanese engine. General Motors 4's and 6's, yes, but not in a Japanese car.

 

I would say you are over reacting, but then again I can't feel it. This engine has VTEC, and vibrates a lot because of this, but I think it is controlled well for what it does. The camshafts are high RPM camshafts with 3 sets of lobes for low and high rpms. If the engine just had the high RPM lobe set it would idle horrible, so a second mild lob set is installed for better idle, this is a basic description of VTEC, but so you know it operates off of oil pressure from engine speed. A lot of this also depends on your motor mounts, and if they are like what is found on a Lexus or Mercedes the engine can be rough and you wont feel it. I think the vibration you feel is part of the car, I notice it in mine. Acura could probably have designed better motor mounts to combat this, but I think it gives the car a feeling of power. I owned a Jetta with a VR6 and that engine was way smoother then this one, and that car was 70% the price of this one, and 100 less horsepower. The Engine does well for how it works, the VTEC technology is hard design and implement, and it doesn't produce a smooth idle, I would say that the trade off in efficiency is worth it. If the engine was as smooth as the Lexus I would say that the TL would be a pretty boring car, I think that part of the fun is feeling the power, and I think the car was designed like this on purpose. Those of you that had the old muscle cars might remember the lope of an engine with a high RPM, high lift camshaft. The TL incorporates that but smooth's it out with technology.

 

Mine has the engine idle buzz as well. In fact, my driver vent (closest to the window)started to rattle when I was sitting still. It has not rattled since so I haven't worried about it. The buzz from the engine is mainly noticeable with the a/c on.

 

This has been my experience with my 2006 as well.

I suspect the rough idle at cold start probably has to do with the engine mounts. The ECM/PCM controls vacuum to the (active) engine mounts so they are stiffer above 1000 rpms and (supposed to be) softer below 1000 rpms. Since the rpms are a little higher for a short while after cold start, the mounts may not "soften up" although you would think they could have the ECM/PCM control the mounts differently during cold star.