I picked up my new 2007 Enthusiasts Z only yesterday. I will start by saying that I am a new stick driver. I had a little experience (basically one time) before getting into my Z, and had someone go over things with me when I picked it up.

Today, after another little practice session I was out on the road driving home when a very odd problem cropped up. First I made a left turn out onto a road, shifted to second, and started accelerating (after the shift) and once I got up to about 21-22mph the car started bucking wildly (almost like it bucks when you shift into 1st when just learning how to drive a stick). I stopped at a light and accelerated again....same thing once I got up around 20mph in 2nd, so I shifted up to 3rd and got the same violent bucking when I got into the mid 30's mph. Both times the bucking did not occur while shifting, but rather a few seconds after shifting when I was already in gear and accelerating.

I pulled off the road and shut the car down and let it sit for about 5 minutes, and then tried again and the problem was gone. I had just been practicing starting and stopping on a hill in a parking garage so I had just been using the clutch a lot. Is this something wrong with the car or could it have been something I did wrong driving? I can't think of any reason it would start bucking violently like that while I'm just driving along in gear.

Also, when I'm cruising around in 2nd in a parking lot I can hear a very soft "grinding" noise that sounds like it is coming from the rear of the car. I am unsure as to whether or not this is the rear axle "clicking" I've heard mentioned with the '07s or not, because as I said I'm still new to the stickshift thing and am not really sure what sounds are "normal". Also, the sound lessens if I push the clutch in.

 

did you put an aftermarket intake in the car?
The AEM cold air intake will take in water, and will do exactly as you are describing.

 

Do you know what RPM you were at? You experience the "bucking" in first due to a combination of real low rpm and too much/too little gas. I don't ever remember experiencing this in 2nd and 3rd gear but I assume if the rpms are low enough...

 

Whitezon:
The car is bone stock. I did drive it once in the rain but did not hit any real puddles, as I was advised to make sure and avoid this in the Z. It was not raining when the problem occured.

abnorm:
I only got the bucking issue in 2nd and 3rd gear. I didn't try and go higher though as I was afraid to push it. I don't recall the exact RPMs but I believe they were believe 2k and 3k.

 

sounds like a safe mode in a sentra... does the z run on a MAF?

 

VDC or TCS kicking in maybe if you let the clutch out to fast depending on RPM???

 

Agree.

Probability of a bad transmission or clutch: 5 percent.
Probability of driver error: 95 percent.

The car will react violently if you attempt to accelerate, and the RPM is too low. Experience will fix it.

 

Can I really have my RPM's too low in second gear though? It was happening after I had been in gear for a few seconds too and accelerated almost to the point of shifting to the next gear, so I'm guessing I was at at least 2500-3000rpm when it started bucking.

As I said, it's perfectly plausible it was driver error as I really still have little idea what I'm doing, but it does seem a little coincidental that I drove it for a day and a half without this happening, then it happened three times in a row, and then didn't happen again after I shut the car down for about 5 minutes.

Could it be related to that grinding I'm hearing while rolling around in second or is that likely unrelated?

 

Get an experienced stick driver to drive your car around the block or something. And see what happens.

 

that is driver error. There is quite a bit of torque in 1st gear and if your not used to it, something as simple as a bump in the road will cause you to push down on the gas too hard. Well, after you relase off it the car will jerk back and you will try to compensate with more gas untill your in an endless process of "bucking back in forth" It's a rookie stick driver mistake that is common, next time it happens take your foot off the gas and push in the clutch. (or switch gears) that will cure your problem.

 

PLEASE do as the man says.

It's very unlikely there is anything wrong with the car. Doesn't anyone remember making the car buck when they first started to drive?

I've got a simpler test. Take your foot off the gas. Does the bucking stop? Problem solved.

You just have to be smoother with your throttle application. Get someone experienced to spend an afternoon giving you some pointers or take a driving skills class.

 

I don't know many people locally that can drive a stick but I found a guy at work. When I mentioned the problem he said basically the same thing as you guys....that my RPMs are too low. When I mentioned the part about it only happening after I had been practicing starting on a hill for a while even though I've always driven it the same way he said that may be because the clutch was more sensitive than normal since it was so hot, but wasn't sure if that could make a diference or not.

So basically, I think I am shifting too soon. I had read through some threads on here about shift points and thought I remembered people were saying they were shifting at around 2500-3000rpm or
so when driving passively. The guy here at work (he drives a 300 Z) mentioned that 'normal' shifting in a car like mine should probably be closer to 3500-4000rpm at the lowest. Does this sound about right?

Also, so when you guys are cruising around a parking lot or really slow road at 20mph or so are you in 1st or 2nd? I was under the impression that first was basically used almost only for starting and that you should shift to 2nd almost immediately and rarely ever downshift into 1st. Is this incorrect?

 

Don't get too caught up in the exact rpm. The car is actually very forgiving. Too low would be trying to accelerate from 1500rpm in third gear or higher and would never alone cause the car to buck and surge, rather just bog (hard on the gears).

You need to focus on what your feet are doing when this happens. What the guy said above about your foot bouncing off the gas pedal is spot on. When you feel this start to happen, let off the gas and push in the clutch.

That is dead on correct. 1st just to get you rolling. 2nd if the car is already in motion. If you are going really really slow (under 5mph) and are uncomfortable downshifting, then stop the car completely and shift to first to start off.

 

learn how to drive

 

really helpful dude