Faulty Clutch/gearbox?

[Yawn]

Hey guys, nowadays when my car approaches (around) red line and i shift from 1st to 2nd, the car sort of stutters and theres a lag (complete loss of power in that 0.5 secs) before it engages 2nd gear. It doesnt happen when im driving it normally but only when i shift the gears quick up high in the revs. Is it to do with my clutch or wat? Its nvr happened before so im unsure.. Thanks in advance for any help

Cheers

[RANDY]

So where does the "no power" start?

At redline before you push the clutch in, or

at redline after you let the accelerator off, or

after engaging second gear?

Option one could suggest coilpacks or whatever the other causes are, the typical stuttering at a certain rev-spot (search for threads relating to this)

Option two could involve an atmospheric BOV that is releasing air out instead of back into the system, so the ECU gets messed up looking for the expected air that has gone missing. (overfuelling at that point I guess)

Option three could be the turbo needing to spin up again, and if you have no BOV or a faulty one that makes the chopping noise, the air is actually spinning the turbo wheel the wrong way, and will make spooling it up again quite labourous and time-consuming.

[Yawn]

So where does the "no power" start?

At redline before you push the clutch in, or

at redline after you let the accelerator off, or

after engaging second gear?

Option one could suggest coilpacks or whatever the other causes are, the typical stuttering at a certain rev-spot (search for threads relating to this)

Option two could involve an atmospheric BOV that is releasing air out instead of back into the system, so the ECU gets messed up looking for the expected air that has gone missing. (overfuelling at that point I guess)

Option three could be the turbo needing to spin up again, and if you have no BOV or a faulty one that makes the chopping noise, the air is actually spinning the turbo wheel the wrong way, and will make spooling it up again quite labourous and time-consuming.

Hmm well i would say its after engaging 2nd gear.. But now that u mention it i also feel a slight loss of power after say 6000 rpm. from idle to 6000 its all increasing then from after around 6000+ it seems to sort of become rather flat then when i shift and engage the no power starts. The no power area feels like a car stalling.. The bov seems to be working fine so im still pretty unsure as to wat it is.. =/

[RANDY]

Ah, might want to check that post about missfire around that rev-range? http://www.skylinesaustralia.com/forums/in...showtopic=32356

Your boost will be dropping off around that stage anyway, but if it's really noticeable, it might be another problem? You're not using a bleed-type controller are you?

[RANDY]

Oh, and when you say that the BOV is working, is it an atmospheric BOV? Might be worth a shot sticking a stock one on for a test?

[Yawn]

Oh, and when you say that the BOV is working, is it an atmospheric BOV? Might be worth a shot sticking a stock one on for a test?

yeah its an atmo one. problem is i dont have a stock one heh the bov came with the car.. also im not really familiar with misfire.. what are the signs of misfire? is there anything audible or maybe a diff sort of feeling? thanks again for the help randy appreciate it

[Yawn]

o yea and its not the clutch slipping? i have no idea what happens when a clutch slips either so plz enlighten me =P

[RANDY]

If it's going to slip, the engine will rev much quicker to redline, and you'll have stopped accelerating by 4000rpm i'd guess.

It's a good point though! Misfiring will feel like you have switched the motor off, or it has stalled, and then it will come back alive.

If you're still getting full noise from the motor when the power goes, then it could very well be a clutch issue. Especially if you whack it hard into the next gear and keep the boost semi-built up.

Find a slight hill, get up to cruising speed in 4th, then put the boot right into it, watch the revs if it's safe, and see if they slip right through.

That's one way, there's another that involves holding the brake and accelerator while in 1st or 2nd gear and cruising.