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Edit: That should have been, "Why does civic responsiveness fluctuate."

Okay, I am talking about all civics, not just mine. What I'm getting at is that when you drive aggressively, the car becomes very peppy and responsive. But when you take it easy on the car, it becomes slow and sluggish, and you have to work the engine to get back it's responsiveness. I thought this was the case only with auto's --I used to own a 98 dx-- but my current 97 dx in manual does the same thing.

There seems to be some sort of "driver friendly" computer in there that adapts to your driving habits. In other words, the computer has you by the *****. Why can't my civic be peppy all the time??? Also, what is this computer called?

 
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driver behavior is one of the many things the computer does to learn and program its fuel and ignition maps. among other things, the way you drive your car will determine alot about its responsiveness and fuel economy. The civic isnt the only car in the market that does that, just about all cars do. Some automatics will do the exact same thing for the transmission too, learning when it should hold gears or shift. I think GM calls it adaptive learning. but all manufacturers have a variation of their own. When you disconnect your battery, your idle and radio stations arent the only thing you lose. You lose the status of all your readiness monitors (which is what your car uses to determine it's emission status) and all your driving parameters. All the engine sensors plus your driving will determine how the computer will relearn its maps. I was just diagnosing something like this for a friend the other day, and when i hooked up the scanner, it was really cool to see the adaptive learning feature alter shift points, shift durations and fuel trims.

 
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Okay, that was VERY informative, but I'm also wondering what your personal opinion is on that feature. I know it varies from car to car, but is it really a good feature? The reason I ask this question is because my friends 94 Saturn SL (manual) seems to perform consistently, with exception to weather --hot weather will make your car feel more sluggish. But the driver doesn't come into play with that car, it just maintains the same performance independent of the driver. I'm sure older cars are ALL like that. The Saturn also gets the same gas mileage as the Civic: 38 on highway, 32 in city.

Regarding automatics, I noticed that my 98 developed --what I thought at the time-- tranny slippage. In fact, what was happening was that I was taking it too easy on my car, and it wasn't shifting crisply and quickly. Conversely, when I drove the car harder the tranny had zero problems shifting. This is when I first started questioning the usefulness or refinement of the driver behavior computer. My experience was later confirmed when I was told by a friend that his 97 accord had the same problem, but that it disappeared when he drove the car more aggressively.

This is NOT just a small issue with the auto's. The manuals, when driven too softly, will be difficult to take off in. The 6th gen civic (if not all civics) require a fairly high rev in 1st to get a smooth take off when the clutch is engaged. This can be difficult to achieve when the behavior of the car is always changing because foot location in relation to the car having been driven hard or soft will produce a different RPM, and the rate at which the RPM's climb in relation to X pedal position will be faster or slower. My point being that you should drive both manual and auto at least semi-aggressively to meet proper tranny requirements.

The question is, in relation to the driver behavior computer, were civics designed to be driven semi-aggressively? My answer would be yes, because the automatic transmission AND manual transmission both work properly this way. And therefore, I conclude that the feature is a negative thing, at least to a point, because you are forced to drive your car semi-aggressively, and that's not always desirable.

What's most fascinating is that I don't notice a drop in gas mileage when driving semi-aggressively. The car drives, shifts, and feels better, and so does the engine.

 
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1 more thing I want to bring up is that if you find it difficult to take off in your manual, and you are experiencing shaking, then you aren't giving it enough RPM and you aren't sinking the clutch in there enough. I posted about this a while ago, thinking there is something wrong with my clutch or tranny, but it's just that I was driving the car too soft, and when you do that, it makes it more difficult to rev properly in neutral for 1st shift. It's a psychological thing mainly, and an actual performance shift based on the behavior computer, as I said before.

 
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yeah i noticed this too. there are times when it feels so bad that im like is this the same car? i have to take it out at night and beat the crap out of it, then it is back to normal. i noticed with the brakes too that happened on the same night, they had no stopping power almost until i started braking really hard and then they were fine again. maybe that has to do with the power assist feature. so idk, it def learns and changes the fuel curves except it does have a hardwired map for full throttle that is used as default and cannot be changed normally.

 
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Thats funny ... i thought my civic was the only one that had this problem ... but turns out its the case with all 4 cylinder cars ... Although this never happens on my 04Altima 3.5 Se or on my uncles 07 Sienna minivan which is also a V6.

Usually when my gas is below the quarter the car is more responsive .. let me tekll u another funny incident. i remeber one day my car waS feeling extra peppy and i met a guy with an AUTO scion TC on a stoplight ... I beat that guy constantly at 3 stop lights ... a few days later ... my car was .. lets say not in the mood ... I lost with another automatic TC like 2 car distances

 
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haha. i swear even on the same drive sometimes when i get on the gas from a stop, ive chirped the tires in my auto, other times it felt like something was pushing it back. its like the engine timing gets caught at the perfect moment when the piston is in a certain spot lol.

 
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yeah i had a thought about this before..i guess i wasnt the only one noticing this lol

 
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you were probably just burning the glaze off the rotors. and WOT fuel trims are most definately not default, they are basemapped and learned just like any other cell in the table. The only difference being that at WOT, the car goes into open loop enrichment and disregards secondary O2 sensor readings because the a/f mixture goes from oscillating rich/lean to steady rich. It WILL try to keep the ratio conservative, because the catalytic converter can be damaged withing seconds if the ratio is excessively rich. But again, the car still has to learn the appropriate crossover patterns for closed to open loop operation and vice versa. It's good to floor your car occasionally not only to help burn up some carbon build up but also to make sure the computer is capable of handling it so that it doesnt stumble over itself when you do floor it.

 
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ah okay thanks. i didnt think the wot trims were learned each time. and yea i do try and floor it every once in a while to keep the engine in good shape.

 
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Thanks for the comments and advice on flooring it. I never do that, but I do push it hard sometimes.