transit6404

So here's my story, it's been snowing a lot for the past 2 weeks here in Ann Arbor, Michigan. For most of the time, especially in the morning when I had to get to work, the roads were not cleaned up. I own a 2004 MT and whenever I started off from the stop, the VSA kicked in.

I just wonder if it is bad for the car that almost all the time the car is at VSA mode? Also, i've noticed that I used up more gas than before the snow storm hits, any guesses?

Thanks

LukeaTron

Not bad for the car at all. It's just cutting the throttle to prevent you from spinning your wheels. No different from just letting up on the gas peddle.

Cars always use more gas in the winter. More time at high idle. Lots of creeping around at low speeds. Crappy ethanol gas. There's a lot of reasons for it.

Daffunda

Actually.....

The VSA uses engine (throttle and fuel) and brakes to limit wheel spin.

Problem with engine limiting torque too much for a too long duration leads to heating up the cat. Doing this excessively, (for like a minute straight and repeat several times) really heats up the cat, which decreases life of it.

But I don't think anyone uses vsa for that long.

I'm not an Honda engineer, but I do powertrain work. Usually VSA shuts off if it gets to that situation. (I think)

nbtx

Please cite your source for your comment on cat heating - that's something
I've never heard, and I doubt it happens because the VSA controls throttle plate opening which the driver does when there is no VSA active control.
The other part of VSA is individual wheel braking which has nothing to do with cat overheating.

tsxk|d

transit6404 i totally understand i'm in the michigan area to by the metro detroit and my gas consumption always goes up when we get one of those storms i normally hit 210-220miles before i get to half a tank. today i look and i was in 115 miles this always happen. My VSA is always on when i'm driving to work when i'm driving back home i like to turn it off, and have some fun turning


05 TSX, 6MT
DIY Intake
Everything Stock (For now)

Daffunda

Throttle opening is not the only way you limit engine torque output.

Fuel and spark timing is also used, depending on how the engineers calibrate the ECM. Throttle alone does not result in cat overheating. I don't know if VSA for TSX uses Fuel and/or spark timing if any, other than throttle and brakes to limit output torque, but if it does, there is a potential for cat to overheat if it does it for a long periods of time continuously.

But I'd imagine honda engineers know that, and have some kind of logic in the software that shuts VSA off or something. So I'd say don't worry about it.

If you want to know, I do powertrain (engine/trans) software work for the major auto company. Call me bs, I don't give a rats ass... I'm just telling the OP what I know.

LukeaTron

With the drive by wire throttle on this car, there isn't much need for screwing with the ignition timing or fuel injectors. It may do it briefly when it first engages to get a faster response but the computer controlled throttle should be able to rapidly take over limiting the power output after the first fraction of a second. I think the problem you're describing with the overheating cats is more of an issue on cars where traction control is kind of thrown in after the drivetrain has been designed. The VSA system used by the TSX is built into the engine and it's software from the ground up.

nbtx

Ok then, it sounds like everybody has an opinion, but nobody has hacked into the ECM software to know for sure. Use your vehicle as you see fit, the cat is warranted for 80k miles. I'll bet it lasts that long no matter how often or long the VSA kicks in.