howardlee

I just got this car 5 month ago, about 10K mile on it. I recently notice a problem, when I hit break, the RPM will go up slightly. This will happen even I am on a flat road. And If I go downhill, for example I go about 50 MPH, and had around 2500 RPM. If I hit the break a little bit, the RPM will shot up to 3500, and stay there even I do not step on the gas. The RPM will only go down if I step on the gas to force it shift up, or when I go back to flat road. I do not know a lot about cars, but from my driving experience, I do not think this is normal. Please help me on this problem. Thank you very much and have a nice day!

drunkm0nk3y

is this a manual or auto?

you may just be hitting the gas pedal at the same time as the brake?

ttk5

I highly doubt this is caused by him "accidentally" pressing the gas pedal. Strange problem though, never heard of anything like it

march30th1988

I have this too. I believe it might be the i-vtec? if you down shift, the rpms go up, and ive seen this as well. I believe when you break, it's lowering itself to the lower gear so it hops up just as if you would downshift on a manual.. it should be natural though, dont think its an issue.. hope that helps

bjohnston115

your car isn't breaking correcting? You are hitting the brakes?

DJMcGee

Exactly per March30... When you BRAKE, the transmission will down-shift through the gears causing the engine RPM to rise and fall then rise and fall as you work your way down. This is normal of today's automatics.

pinatubo

The question is that does it happen on every other automatic transmission vehicles or just TSX?
I don't remember that happened on my Accord previously.

howardlee

It is automatic.

By hit the break, I mean normal break, just like when you are getting to close to the car in front of you.

I also driven some newer model automatic, just not Honda. I do not notice this kind problem.

Thank you very much for all the reply.

DJMcGee

Our Honda Odyssey (5 sp) shifts down very similar to my TSX. I think some of it is an issue as to whether you notice it much or not. Like a lot of car things it bothers some and not others. If you really aren't sure you could swing by the Acura dealer and drive another car and see if it does it too under your style of driving.

One of the issues with a problem like this is that it is very driver specific.

MrOtocinclus

From Acura.com:

The Grade Logic Control system monitors throttle position, vehicle speed, acceleration and deceleration in order to recognize steep inclines so it can avoid gear hunting.

Edit: Honda Accord circa 2005: http://www.hondacarforum.com/honda-2...c-control.html

howardlee

Thank you MrOtocinclus for your information.
It look likes match my problem.
I think I am going to do more research on this topic.

hondu

Not sure if you can really call it a "problem" yet.

GrigioX

for what it's worth, my Audi does the same. It upshift when braking on a downward slope. It also holds a higher gear longer when on an upward slope.

My TSX does the same as what the OP is bishing about.

fallacy

I have noticed the effect is far more apparent on the 2nd Gen TSX than my 1st Gen. I actually like when this happens as I don't have to ride the brakes as long since the engine compression is aiding braking.

Colin

This is normal and not a problem. Grade Logic is downshifting (moving to a lower gear) to help maintain the vehicle's speed without you having to 'ride' the brake (vs. break) all the way down the hill. All Acuras have had this feature (not a problem) since the mid-nineties (at least). Relax and enjoy your TSX

march30th1988

haha, excuse my poor use of vocabulary.. I meant BRAKE, not break! I still have problems with using this word on the forums.. hahah!

HondaOnWORKS

The sports mode on automatics for both CL9 and CU2 vehicles will do that. It isn't problem, the car downshifts automatically for you when you go under a "X" MPH, and won't let you up shift you don't go over a "X" MPH. Its to protect the car, and transmission. Also full stops will bring you back to gear 1. Also if you hit red-line the car will disconnect you from the fuel I believe to stop you from hurting the engine.