So i'm having a strange problem when in 2nd gear and up. The trouble is that if i'm cruising along and try to overtake a car and punch the gas, it seems as if the tranny shutters between 3500&4500rpm and then places itself ? Now my mechanic took a quick test drive and says its doubtfully not the clutch, he says it grasps very well. any suggestions? He's going to scan the car wednesday to see if anything comes up or is stored in the car.

 

can it be my vsa or lsd acting up ?

 

It's as if you posted this for me...
I only notice it in 4th gear, but when I am cruising back roads and hit the gas a little out of a turn, the tach surges about 300 rpm and then settles in and the car begins to accelerate.

 

exactly, only mine does it through 2-3-4gear. I'm determined its a sensor, either brake sensor or yaw sensor. It only occurs when i punch the car, so i suppose there is a protection kicking in to override the heavy acceleration.

 

Perhaps the late-night members will weigh in?

 

If you have a manual and your clutch is fully engaged, then it's slipping. If your tach suddenly shows an increase in engine speed that does not correspond to road speed and you are not in the process of shifting, your clutch is slipping. There is an outside possibility that your LSD is slipping but I seriously doubt that.

Try this. Find a fairly steep hill and hit the bottom of the hill at at enough speed to where you are in third gear and your engine is turning between 3000 and 3500 RPM. Now floor it. Id your engine speed suddenly increases more than it should in relation to road speed, your clutch is slipping.

 

A car with a manual transmission has, in effect, a direct drive system between the engine and the drive wheels when the clutch is fully engaged. In other words, the engine is mechanically locked to the drive wheels. There is nothing in between that can slip or cause engine speed to race ahead of the road speed except for the clutch and if that component is working properly, everything is locked up tight.

What concerns me in your description is your use of the word "shutters" followed by "places itself". Do you notice anything out of the ordinary under normal driving conditions? Any shuttering when starting out in first gear (especially on hot days or when you have been in heavy traffic)? What about when aggressively shifting when running through the gears at WOT... anything unusual or strange when doing that (it's normal when doing this to feel the clutch seeming to not grab hard)? And what about normal but semi-hard acceleration in the RPM range you reported? Suppose you are at a light and you are not paying attention when it turns green and accelerate a little harder than normal to catch up to traffic... would that cause what you are reporting?

 

Kind of a stupid question but are you sure your VSA is off when this happens? The first few times I went to accelerate rapidly in mine it would do the exact same thing until I figured out the VSA was keeping me from going vroom. lol

 

no, i've tried with vsa on & off and got the same result.

"A car with a manual transmission has, in effect, a direct drive system between the engine and the drive wheels when the clutch is fully engaged."

So what your are saying is that if it is fully engaged, foot of the clutch just cruising along, and i decide to punch it it shouldn't have any slippage?

 

http://s30.photobucket.com/albums/c3...1108-00007.mp4

 

Correct. If it does, something is wrong.

When the clutch is fully engaged, the entire drive train is locked and you have a direct path (drive) to the drive wheels. If your engine speed suddenly increases out of proportion to your increase in road speed, something is slipping.

 

What is the clicking sound?

If you were in the same gear the entire time and didn't touch the clutch, it is slipping. But there is something that doesn't look right to me.

You first hit the throttle at around 2200 RPM but after the several times you did this, your engine speed dropped down to 1200 RPM then settled in just above 1000. What happened? Did you disengage the clutch?

 

the clicking sound is me changing gears. i went till 4th gear

 

looks like a slipping clutch to me.

when the revs go crazy the speedo doesnt move accordingly and instead moves sluggishly up.

 

Yep. Not good.

 

there isn't a possibility that this could be a throttle problem? Or a fuel system/combustion problem.

 

If your clutch is fully engaged and not slipping then you have effectively locked your engine to your drive wheels. It's as though you had a solid axle from the crankshaft to the CV joints. There is nothing between these items that is going to allow the engine to suddenly rev up providing everything is working as designed. So if the engine does increase speed out of proportion to wheel speed, then something is slipping and almost always, that is going to be the clutch.

 

yup. If your clutch is fully engaged (pedal out) and your MT is acting more like a CVT and the revs increase while your speed is slowly increasing or remains constant, your clutch is slipping.

to the OP i would get this fixed asap. I've read here once it starts slipping it deteriorates rather quickly, and you're also potentially damaging the flywheel.

 

Is it possible to only have this problem occur in 3 and 4 gear only? 1,2,5,6 are all good in my case. It is also a very smooth extra rev and doesn't feel mechanical...

 

it can happen when the load on the transmission or power from the engine is greater than the clamping power of the clutch.

for example it will be more likely to happen driving up a hill or an incline than going downhill, or if like the OP, floors the throttle. It is not necessarily dependent on the selected gear. I'd almost think it's more likely to happen at higher gears since it's harder for the engine to increase the wheel speed. Once you apply power in a higher gear, the transmission encounters more resistance to spin the wheels. At this point the clutch is the weak point.

this is why starting from a stop in 2nd or any other higher gear is not advised. Either way, uncontrolled revving with the clutch fully engaged is not normal operation and needs to be looked at.

if you cant take our word for it:
http://www.youtube.com/watch?v=r837lj8jtO0

 

cant edit:

video of a slipping clutch which looks strikingly similar to OP:
http://www.youtube.com/watch?v=jxKyU-Xjb5k

 

well i made an appointment at my dealer to go for a test drive with a mechanic, get them to diagnose it and identify the problem then off to my mechanic ;-) with the results. I'd rather pay 55$ then 95$ an hour !

 

Did the test drive turn into a vacation? Haha. What did they say?