Hey guys, just a quick question (I did some searches but got the phone book). We bought our TL new in '07, and it presently has 80K on the clock. It runs well, but the acceleration isn't quite as smooth as it used to be. I cleaned the TB probably 10K miles ago, and it has a new AF, so I'm figuring plugs next. Does this sound about right to you guys, or is there something else that can cause the acceleration to be not quite as buttery smooth as it was when the car was bought?

P.S. 93 octane only, and always at the same station.

 

Is there a certain RPM range/throttle pedal position/gear where the acceleration isn't as smooth as it should be or it seems to affect the car no matter those values?

 

Good question. Not really, it's in all gears, and as the revs rise. I don't even notice it unless I have to pull out in traffic and give it some stick, and the rpm climb looks perfectly smooth, but there are dips that can be felt.

 

Does it happen in sport shift mode or in automatic only?

 

The front side plugs are easily accessable, pull one and inspect it. I swapped mine out at 105k and they looked perfectly fine.

 

I never use sport shift

Guess I'll pull a plug or two to see what's up. Anyone know the factory gap off hand?

 

A very common issue on our cars is the APP sensor. Not that you should go throw 100 dollars at the issue right now because it might not be your problem, but keep that in your mind as a possible cause. Mine started out as little less power feeling, then started to be jerky acceleration. Changed the APP and it was like new.

If changing the plugs doesn't help... I would look here.

 

Try in sport shift to see if there's one gear that's especially slow feeling. As erg69 noted the app sensor comes to mind. You can test it in 2 ways with a multimeter. Ignore the HDS section.

Gap is 1.0-1.1mm when new for the spark plugs.

 

Might take a look at the EGR valve.

 

^ I think EGR would throw a code before he could feel it.

 

Not always. Lots of times the idle will be rough/uneven and acceleration will suffer way before it throws a code.

 

Just to add to this.......you could try adjusting the cable for the APP sensor prior to replacing it. If the other options don't fix the issue.



https://acurazine.com/forums/problem...-doing-830989/

 

Thanks guys, I now have a clear path as to what to do! I'll update the thread after I go through them one by one.

Much appreciation .