like the title says, the car always needs to downshift whenever i slightly gas up on any speed. anything under 2k rpm on any gear, it always needs to downshift to get it to accelerate. my car feels like its struggling on its highest gear. its driving me crazy since i just did all the necessary maintenance not too long ago.

heres more info on the car:
2004 tl 5AT with 87k miles
always use 93 premium shell gas
used to run perfect now it feels like its on limp mode

past 2 months have done the following:
timing belt, idler, tensioner, thermostat etc.
valve adjustment
coolant flushed with factory oem coolant
replaced trans fluid with redline non fm type f atf 2x3
redline 5w30 oil with sk2 royal purple filter

nothing seems to fix it. theres no check engine light or anything that could steer me in the right direction. what needs to be done, can anyone help?


ive searched but cant find any thats similar to my problem.

 

More EtOH in the gasoline now... could be why you feel it at the pedal.

 

I'm experiencing the same thing. I have about 114k miles right now. I haven't done valve adjustment or thermostat. Could it be the type f redline fluid? I've tried playing with varying levels of the fluid and it makes a difference somewhat. Hard to explain.

 

It's impossible for the trans fluid to do this unless the trans is slipping which is highly unlikely on that fluid.

This is interesting. I would look at the valve adjustment first. Usually you'll get a misfire if it's way off but not always. How is the idle?

 

valve adjustment has already been done. mechanic said only the exhaust was out of spec and adjusted it. at cold idle, the car inconsistent vibration and intermittent sputtering at park or in gear.

 

I'm sorry for your troubles and only here to give my best advice to your issuse.

Who did the T-belt and valve adjustment?
Did this issuse start after that service?

If so they may off a tooth on the timing belt or have the valves adjusted too tight.

In general how does your transmission shift?
Harsh, smooth, delayed?

I doubt the transmission has anything to do with your loss of power since it's ability to shift isn't a concern.

You may want to do a gas pedal reset test.
There is a thread on this: https://acurazine.com/forums/3g-tl-2004-2008-93/resetting-ecu-makes-me-happy-747662/

What this is... Your vehicle learns how you drive. It knows if your an aggressive driver or not and over time this is the norm for the system. By doing a simple proceedure you will reset the pedal and your vehicle will run back into re-learn mode. You should notice the vehicle perform better.

Proceedure as followed: (Copy and pasted from link)

turn the key to the second position make sure everything is off like radio ac and so on... take it out put it back in and then again to the second position and press the gas pedal for like 30 seconds... i do it for a minute just to make sure. Then simply turn of take the key out put it in and turn the car on.

Let us know if this solved your issuse.

 

The job was not done right. As I stated before T-belt may be off a tooth or valves completely adjusted wrong.

Ive done valve adjustments on a few TL's and can clearly tell you that intakes are more common to be out of adjustment due to "Vtec" than exhaust valves.

If you have the time you may want to check my thread about valve adjustment and it's proceedure.

https://acurazine.com/forums/3g-tl-2004-2008-93/yayy-valve-adjustment-pictures-inside-725750/

The proper way of adjusting these valves right from the Honda/Acura tech manual is "Adjust at cold spec, Optional to readjust after start up" Your not suppose to only adjust one side both must be adjusted...

 

I have the exact problem as OP.

I also changed the timing belt, tensioner, spark plugs, air filter and a engine treatment offered by the dealer.

It didnt help, but i did notice one odd thing, when i have less than 1/4 of gas the car runs fine, as soon as i put in 5$ of gas and it goes higher than 1/4 i swear i can feel the difference. It feels sluggish.

please tell me i'm not crazy

 

forgot to add, dealer did valve adjustment during timing belt service

 

That's what I meant, it probably wasn't done right.

If you're losing compression due to incorrectly adjusted valves, it will show up as a misfire at idle and loss of power at higher rpms.

Many times exhaust valves being out will be able to be heard through the tailpipe at idle. Exhaust will usually be worse when fully hot and intake will be worse when cold but not always.