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Discussion Starter #1
I've noticed that every once in a while when I floor it, it doesn't seem to have full power kick in. Usually when I floor it, it takes a split second to rev up and you get that nice slam into the seat. About 3-5 times I've noticed it doesn't rev as loudly and the acceleration is off by a nice amount.

If I let it go and step on it again, it will kick in right away.

I'd say this hasn't happened more than 5 times in probably over 300+ wot runs.

Can I chalk this up to the auto trans? Or what? Any ideas would be great.

Thanks all.

-Chris
 

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Mine seems to do that too, not sure if it is exactly the same thing, but mine is a manual so it couldn't be an automatic transmission thing.

I would describe it as "hesitation" -- for example sometimes if I am cruising along at about 60-65 and downshift to 3rd and floor it . . . car should take off, but it hesitates for a second or two or three, then takes off. I haven't tried a repeat to see if it only does it once in a row.

I was thinking it might be detecting a little knocking, pulling timing and causing the hesitation, then advancing the timing again. But I tried a mix of 93 octane on my 87 tune, that should prevent any pinging (knocking) -- and it made no difference, it still did it.

I've seen some other threads that suggest that it might be the ECU "learning" conservative driving, so it is "surprised" the first time you floor it, then it relearns the more agressive driving and it's OK the next time. I'm not sure if this really makes any sense . . .
 

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Mine seems to do that too, not sure if it is exactly the same thing, but mine is a manual so it couldn't be an automatic transmission thing.

I would describe it as "hesitation" -- for example sometimes if I am cruising along at about 60-65 and downshift to 3rd and floor it . . . car should take off, but it hesitates for a second or two or three, then takes off. I haven't tried a repeat to see if it only does it once in a row.

I was thinking it might be detecting a little knocking, pulling timing and causing the hesitation, then advancing the timing again. But I tried a mix of 93 octane on my 87 tune, that should prevent any pinging (knocking) -- and it made no difference, it still did it.

I've seen some other threads that suggest that it might be the ECU "learning" conservative driving, so it is "surprised" the first time you floor it, then it relearns the more agressive driving and it's OK the next time. I'm not sure if this really makes any sense . . .
Just curious, do you guys have TCS on when this happens? I have after market tires on mine and when I punch it in third, sometimes, the TCS comes on gives that hesitation you guys are talking about but when I turn it off, there is no tire spin and it goes just like it should.
 

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Discussion Starter #4
No, I've never noticed the trac light when this happens.
Sometimes, the trac light will go on for a split second when going into second or third. But I usually turn the trac off when I get in the car unless it's raining:bigthumbsup

How often does this happen to you? Are our cars "drive by wire" cars? Could this have any thing to do with it?
 

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Just curious, do you guys have TCS on when this happens? I have after market tires on mine and when I punch it in third, sometimes, the TCS comes on gives that hesitation you guys are talking about but when I turn it off, there is no tire spin and it goes just like it should.

^^^ Agreed. But weird if it's done it 5 times in 300+ WOTs...seems that if it was TCS you would have pinpointed that.
But whenever I'm planning on stepping on it and driving rather spirited, I turn TCS OFF immediately!
 

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My TCS if always off when I drive. Had a close encounter in an intersection when it almost got me hit and since then it has been off.

Next time you are in the car, turn off TCS and see if you notice it. That might be it. I don't have a ton of HP right now and before I started just turning TCS off, probably 1/8 times I would punch it in third, it would do it.

With your gearing, you are getting more rpms when you shift and if you say it chirps in 4th, it could be "spinning" in third, or according to the computer it could.
 

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. . . do you guys have TCS on when this happens? . . . .
yeah TCS could be the culprit but I think I have had it happen with TCS off . . . will need to do another test to make sure! (I love this "testing" ;) )

I gotta get in the habbit of turning off TCS as part of my startup routine. Just yesterday I had a Civic TSI (? the sporty one) give me a big glare then take off at high RPM . . . I figured I'd just hang right on his tail for fun . . . but as I pulled out of the parking lot I hit a little sand and the TCS kicked in and slowed the car down right at that critical moment . . . of course I still kept up no problem without even going WOT but not as close as I wanted . . . so it made me think "dang, gotta remember to turn that thing off" . . . I just wish it didn't turn on the idiot light on the dash, I hate driving around with a warning light on.
 

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Discussion Starter #8
yeah TCS could be the culprit but I think I have had it happen with TCS off . . . will need to do another test to make sure! (I love this "testing" ;) )

I gotta get in the habbit of turning off TCS as part of my startup routine. Just yesterday I had a Civic TSI (? the sporty one) give me a big glare then take off at high RPM . . . I figured I'd just hang right on his tail for fun . . . but as I pulled out of the parking lot I hit a little sand and the TCS kicked in and slowed the car down right at that critical moment . . . of course I still kept up no problem without even going WOT but not as close as I wanted . . . so it made me think "dang, gotta remember to turn that thing off" . . . I just wish it didn't turn on the idiot light on the dash, I hate driving around with a warning light on.
Wow you get a light on your dash? Mine just has the "OFF" lit up on the button itself.

Also, this happens very very rarely (hey that rhymes) but I'm sure the trac was off as I usually turn it off on startup if I plan to do a little performance driving.

As for going out and trying it, it may not happen again for three weeks or longer, but if/when it happens again, I'll make sure to see if I remembered the trac off.

Before reading Jberts post, I was thinking maybe the autotrans didn't shift into the right (lowest available) gear if that makes sense. It's almost like trying to accelerate off the line in say 3rd gear.
 

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. . . Before reading Jberts post, I was thinking maybe the autotrans didn't shift into the right (lowest available) gear if that makes sense. It's almost like trying to accelerate off the line in say 3rd gear.
that might still be it, my issue could be completely different, hope I'm not throwing you off the right trail! :bigthumbsup
 

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yeah TCS could be the culprit but I think I have had it happen with TCS off . . . will need to do another test to make sure! (I love this "testing" ;) )
Did anyone test it to see if TCS was the problem?
 

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Discussion Starter #11
Did anyone test it to see if TCS was the problem?

Yes, the trac was off. It actually happened two times during one trip a few days ago. I noticed it seems to do this when I'm driving faster than 55mph and floor it. It's never happened under that, at least that I can recall.

And this time, instead of letting off the pedal, I held it down and it did finally rev up and kick, but after like 2-3 seconds when it's usually almost instant response.
 

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Yes, the trac was off. It actually happened two times during one trip a few days ago. I noticed it seems to do this when I'm driving faster than 55mph and floor it. It's never happened under that, at least that I can recall.

And this time, instead of letting off the pedal, I held it down and it did finally rev up and kick, but after like 2-3 seconds when it's usually almost instant response.
That is so weird. It might be in your tune or something along that sort. I know with a manual and i punch it in third, even with my 3.55's, it doesn't hesitate
 

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It's your ECM that's the likely culprit. If you drive it around town conservatively for a little while and then try to floor it, you will often get a 1-2 second hesitation. It happens to me. A tune usually helps, but even with a tune it can still happen if you drive conservatively or are stuck in slow moving traffic.

The ECM in these cars is an adaptive computer; it adjust to your driving style. Usually some aggressive driving and a few WOT runs in a row will set it straight again.
 

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I agree with Wildcat that the adaptive learning does this when driving conservitivley around . I also think the auto is a bit of the problem as well . A new torque converter from PI would help alot. My new torque converter sure is nice and when I hit it,it goes a lot quicker. What it does is get you in a higher torque band much faster.
 

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. . . The ECM in these cars is an adaptive computer; it adjust to your driving style. . . . .
so it's kind of like the computer is thinking "ho hum, here we go for another lazy stroll around town, nothing to get excited about . . . " and then all of a sudden you floor it and the computer thinks "WTF????" for a few seconds, then "oh, OK, time to go!!!"
 

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so it's kind of like the computer is thinking "ho hum, here we go for another lazy stroll around town, nothing to get excited about . . . " and then all of a sudden you floor it and the computer thinks "WTF????" for a few seconds, then "oh, OK, time to go!!!"
That's pretty much it. I've driven quietly around town to get better mileage and then tried to pass somebody quickly and have had to abort because of the delay in the throttle response. It's really annoying.
 

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so I did a little more "testing" at lunch time today with the TCS off (car was in "advancetrack sport mode") --

if I am at light throttle and punch it in third, whether downshifting from 4th or whatever, the car does that hesitation thing. On mine it is more like a "bog" but it does not last long; just bogs down for maybe a second or two and then recovers.

I do have the 3.31 gears and I'm at about 3,500 RPM (give or take) when this happens; so maybe I just don't have the revs high enough?

I have not done the ECU reset by disconnecting the battery, not enough WOT runs to get the computer to remember its high performance roots, so maybe that has something to do with it.

Right now I am running the Bama 87 Street tune, maybe I'll go back to the 93 tune (with some 93 gas of course) and see if that does the same thing.
 

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It does this on mine too and drives me nuts. It's all about the ECU and trans... if you leave it in drive and push it hard or even floor it (unless you are mashing it from a dig), it will take a couple seconds to figure out that you really want to go hard and aren't just tapping the pedal on accident. Sometimes, mine doesn't even downshift. At that point, the best thing to do is downshift manually before you punch it. When you do that, you will actually get the near-instant throttle response you are expecting and it will pull pretty good even when you just tap on it. My son loves sitting in the back seat when I do that, makes him giggle his butt off :)
 

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This car does have adaptive ECM and wildcat is right but I have noticed if I kind of feather the gas pedal a couple times before I stomp on it is a little more responsive. Plus it sounds cool.
 

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Discussion Starter #20
Sooo, the bottom line is for me to stop driving normally and keep it to the floor a lot more then right??? :gringreen:winks
 
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