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Old 02-08-2005, 08:59 PM   #1
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low speed = jerkiness???

Everyday, travelling to and from work, I go through about 10-15 minutes of slow speed traffic, sometimes even stopping to a standstill. I own a 2000 Legacy GT with manual transmission, so in the traffic I try to use the clutch as little as possible by staying in gear and travel at a steady pace. But as you know, traffic NEVER travels at a steady pace (otherwise it wouldn't be traffic).

The problem is that no matter how steady and slowly I move the accelerator pedal, I can't get a smooth transition when I try to accelerate or even when decelerating. The car jerks (dips in the rear) as if I just "stomped" on the pedal when accelerating. Then it dips forward when decelerating. It makes me look like a noob driving a manual transmission for the first time. The only way to counter these reactions is to actually use the clutch

I owned many cars with manual transmissions (actually all the cars I've owned were manual trannies) and have a quite a few years under my belt of driving experience and I never had this problem before. Even my Mazda B4000 4x4 is much smoother in traffic than my Legacy.

This is my first Subaru and the first time I've driven AWD. Is this a common thing with Subarus? Is this a common trait of AWD? Or is it just my car and it has something to do with the clutch, flywheel or even a soft suspension?
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Old 02-08-2005, 09:35 PM   #2
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its pretty much all subarus that have turbos. and due to the fact we have ****ty gas here in california that driving is never as smooth.
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Old 02-08-2005, 10:01 PM   #3
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I don't have a turbo! so it can't be that!
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Old 02-09-2005, 06:57 AM   #4
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Mine does it on occasion. I have no idea what the problem might be. I wish I could blame my turbo.
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Old 02-09-2005, 09:12 AM   #5
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So a tap on the gas or brakes is making the whole car jerk? Is there any measurable transition between the time you touch the gas and when it happens? How many miles are on the car?
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Old 02-10-2005, 09:12 PM   #6
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DLC, not tapping, just putting slight pressure on the pedal does it. And the brakes are not involved here. It's all about the acceleration and deceleration at low speeds. I just can't make it smooth enough like I could with all my other cars.

Maybe I'm not explaining it right. I was just talking to a friend of mine about it. This is how I explained it to him. On acceleration, it almost like there's a slight hesistation just after pressing (slightly) on the pedal, then it jerks forward to pick up some speed. On deceleration, it's like the car wants to stop moving or like the engine wants to stop, but the inertia of the car won't let it, which makes the car buck. You have to remember, this is while still rolling at a low speed, probably in the range of around 5-15mph.

I bought the car in August of last year and it now has about 71000miles (i live in Canada so i had to convert kph to mph )
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Old 02-11-2005, 10:30 AM   #7
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Interesting. It doesn't sound like clutch slippage, more like transmission or center differential issues, but those should also have symptoms in other gears, coasting and accelerating, though probably not nearly as bad.
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Old 02-11-2005, 03:05 PM   #8
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OK... i'll have a look at the diff fluids and the levels.

Just outta curiousity... does your car do this? Does anyone elses car do this?
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Old 02-11-2005, 10:21 PM   #9
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my wrx bucks like this when i am going very slow. Seems pretty common
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Old 02-12-2005, 01:44 PM   #10
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Mine is pretty well behaved at low speeds, all things considered. I would almost be willing to suspect something is funky in the engine tune that might cause the problem, but i'm sure you would have mentioned that.
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Old 02-20-2005, 02:07 PM   #11
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My BE does this all the time. Annoying as all hell. I've heard things about drivetrain lash, but I have no other ideas.
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Old 02-21-2005, 05:05 PM   #12
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This is normal for MT Subaru's. Subaru's in general are pretty torquey cars and there is "play" in the gears. Which accounts for the jerkyness, also it's even more jerky with the newer MT subies that have ETC
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Old 02-23-2005, 08:19 PM   #13
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I've noticed a bucking sensation with my '05 Baja Turbo 5spd - sometimes when I accelerate fast and releast the clutch quickly it acts up, also when driving slow and the engine is cold with moderate pedal pressure. I posted a thread on NASIOC and some commented that it may be linked to the drive-by-wire setup. I have driven other manual transmission DBW cars and they did not exhibit this kind of behavior, yet all of the 2005 Subarus I test drove exhibit this behavior (Forester XT, OBXT, Legacy GT and Baja T)

I am hoping that when I upgrade my ECU there is some improvement as it it very frustrating when doing quick shifts and the clutch pedal is fully released to have the car act up.
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Old 02-24-2005, 01:26 AM   #14
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My '05 wrx does it too. Kinda annoying, but oh well.
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Old 02-24-2005, 10:47 AM   #15
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I tested this again and i think i know what you're talking about. I don't drive very much in 1st simply because of the torque the NA 2.5 has. It doesn't mind creeping around a parking lot in 2nd at 5mph.
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Old 02-24-2005, 10:47 AM
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05, 2002, accelerationdeceleration, barely, bucking, bucks, coasting, e36, jerks, jerky, nasioc, slight, slow, speed, sti, throttle, wrx


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