Jerky acceleration when flooring the gas
10-24-2007, 04:06 PM
#23
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Could be the ECU going open loop from closed loop and the A/F mixture is not quite right in open loop. Could also be the Automatic transmission clutches slipping or some traction control problems. Could also be fouled spark plugs misfiring or breaking down.
10-24-2007, 04:37 PM
#24
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Originally Posted by BigMURR
FYI, QT (quicktrip) is top tier so therefor not cheap gas, which is why I get it. What is funny though is the BP the so called "good" gas is not top tier, interesting.
10-24-2007, 05:00 PM
#25
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Originally Posted by WeaponX6X
Originally Posted by BigMURR
FYI, QT (quicktrip) is top tier so therefor not cheap gas, which is why I get it. What is funny though is the BP the so called "good" gas is not top tier, interesting.
I too feel a little jerkiness (both with chevron and QT gas in my car) and I've checked my spark plugs (the gap was only slightly larger). Personally I think it's how our car is made, whether it be mechanical or electrical, and there's not much we can do about it.
10-24-2007, 05:10 PM
#26
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Maybe it's the tiny unicorn in your exhaust and the other one ____ting on your filters! 
From Dane Cook...Sorry.
Honestly i think everyone is looking too far into this. Maybe i'm getting the wrong impression from the description people have explained but the similar feeling i feel is explained to me as a combo of VVT-i and drive by wire. I'm not gonna lose my mind trying to find out what gasoline causes it. I will just accept the barely noticeable "jerkiness" which is only really present when i'm in a gear or two higher than i should be at a given speed and trying to accelerate. For instance, trying to to go from 15mph to 50 mph in 3rd gear.
From Dane Cook...Sorry.Honestly i think everyone is looking too far into this. Maybe i'm getting the wrong impression from the description people have explained but the similar feeling i feel is explained to me as a combo of VVT-i and drive by wire. I'm not gonna lose my mind trying to find out what gasoline causes it. I will just accept the barely noticeable "jerkiness" which is only really present when i'm in a gear or two higher than i should be at a given speed and trying to accelerate. For instance, trying to to go from 15mph to 50 mph in 3rd gear.
10-25-2007, 03:02 AM
#27
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drive-by-wire throttle lag = Santa Claus riding a dinosaur at the rodeo. Check how many $50k+ cars use drive-by-wire. That's not where the problem lies.
"throttle lag" = heavy flywheel on the manual, or the actual automatic transmission being slow (like just about every other auto trans on the market).
As far as "jerkiness" goes, take a look at the motor mounts. They allow the engine to rock front to back VERY dramatically, due to Toyota engineers wanting to isolate vibration from the cabin. Filling them with 3M WindowWeld or similar product will reduce this "lash", again at the expense of engine vibration entering the cabin.
The drivetrain is designed to be smooth and inoffensive, not some rippling snorting monster. Try driving a tC with a super-light flywheel in traffic. Your "throttle-delay" is gone, but the car is hard as hell to keep from stalling.
[/unfounded misconceptions about drive-by-wire]
"throttle lag" = heavy flywheel on the manual, or the actual automatic transmission being slow (like just about every other auto trans on the market).
As far as "jerkiness" goes, take a look at the motor mounts. They allow the engine to rock front to back VERY dramatically, due to Toyota engineers wanting to isolate vibration from the cabin. Filling them with 3M WindowWeld or similar product will reduce this "lash", again at the expense of engine vibration entering the cabin.
The drivetrain is designed to be smooth and inoffensive, not some rippling snorting monster. Try driving a tC with a super-light flywheel in traffic. Your "throttle-delay" is gone, but the car is hard as hell to keep from stalling.
[/unfounded misconceptions about drive-by-wire]
10-25-2007, 03:17 AM
#33
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nice. yeah i walked through there the other day cuz i went there for a game. turns out i missed quite a bit...but you know, i had to suffer through the construction and the middle-of-winter announcements that you need to walk around the WHOLE campus cuz some retard decided to stick his pee pee in an electrical pipe...
10-25-2007, 03:34 AM
#37
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Check or beef up the ground from the battery and the throttle body area - I hear on the tC that you can reduce throttle by wire problems with better battery grounds. I have to say that I don't get any of this in my xB - pulls like crazy right to red line at any thottle opening. If you have some problems that could be spark plug at high RPM and full throttle then try gapping the plugs on the smaller side of the recommended gap.
10-25-2007, 03:55 AM
#39
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I experience the same problem with the jerkiness,
I also think its a vvt-i and drive-by-wire trait.
By the way chevron premium is the best and the cleanest
and I know because my uncle works for LAX in the fueling district
and says that its by far the cleanest when it arrives.
I also think its a vvt-i and drive-by-wire trait.
By the way chevron premium is the best and the cleanest
and I know because my uncle works for LAX in the fueling district
and says that its by far the cleanest when it arrives.
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