Hey guys,
Done a massive search but kept getting different answers (bad clutch, surge compression, boost creep, God knows).

today while driving, I floored it in 5th gear starting at 3000 RPM, then as soon as peak boost picked up at 4000, the car suddenly drops down 500 rpms then picks up normal (wot the whole time, iddnt take my foot off at all). Tried this in 4th gear and same thing. Seems like it does it in 3rd (will feel like it drops not even 100) but too minor too notice in this gear. I then wot at 5000 in 5th gear and same thing, it will pick up normal but as soon as i hit peak boost 1000 later it drops 500 then picks up normal...why is this? definately boost sensitive since partial throttle is fine.


Mods : megan 3" dp, stock cat, HKS Carbon catback, buscher filter on stock pipe, hallman mbc set to 18.5 psi, and basic tune.
happens here to an evo X https://www.evolutionm.net/forums/ev...laination.html

i also googled and found this, http://www.freshalloy.com/forums/arc.../t-182021.html which seems like the most similar situation except for my car will drop 500 rpm then climb to redline, this guys car will drop then climb then drop. both of us can redline without cutout with partial throttle. he tried new spark plugs, maf sensors, and coils, but fixed it by pulling his ecu (???) so does i need to get retuned?
Ive had these same mods for almost half a year now with no problems until today. I appreciate any help, thanks so much!

 

sounds maybe like your clutch is slipping, kinda hard to picture what you are talking about...

stock clutch?

 

Sounds like your clutch is slipping but instead of noticing the slip, you just see the RPMS dropping back down as the clutch starts to grab. If you go out and try this again, check to see if the tach starts going up without the speedometer going up.

 

Beginnings of clutch slip. Time to get a new one.

 

but i thought when the clutch is slipping, the RPMS shoot up and the car jerks you back in your seat, without actuall goin anywhere. my rpms will go down, feeling like if fuel stopped

 

Does the car slow down when the RPMs drop?

 

Like the other people are saying, it sounds like your clutch is slipping for a second during spool up, then finally grabs. Which would explain the 500rpm drop you are seeing.

 

If the revs go up but the speed doesn't what else could it be? Face reality bend over and hike the wallet. If clutches were cheap you would never see these posts.

 

it might be your spark plugs, check them! how many miles on your car?

 

Are you saying that you car falls on its face, total loss of power?

If not, your clutch is slipping the whole time and finally grabs at a higher RPM because your torque is dropping off in the higher RPM range.

 

how could this be possible? please tell me the physics behind it.

 

your going to need a new clutch

 

but you're misunderstanding my situation. actuallly, the opposite is happening. My revs do down 500, instead of up, and while it goes down the car doesnt slow down, its like its in nuetral, then it picks up regular. so it picks up, goes down then picks up. so my speed is actuall goin up, and my revs only go up along with the speed. thats why this is confusing

 

the tach will go up, then will go down with speed staying the same only for about a split second, then will go up. i think the whole clutch thing is when u step on it and your revs go up but car doesnt move faster. this is different which is why i dont think its the clutch, but im not ruling it out

 

no its like the clutch is grabbing (car is moving) then the revs go down for approx 1 second which feels like neutral then picks up again