Hello everyone,

I've been reading these forums for quite a while but I haven't really gathered up the courage for some tuning or anything yet, since my car is still under warranty (3 years in europe - any modifications would make it void).

I drive an Evo VIII (05). Recently I started noticing that when I'm applying throttle, there seems to be a gap in accelerating whenever there's high amounts of boost. For example driving in gear at revs lower than the turbo hits already and then accelerating, the revs will move nice and smooth to a point where u can hear the turbo kick in - the revs just jump for no reason for about 1k and then reduce and then steadily increase again.

Example would be: 3rd gear, 2500 revs, then adding throttle. Revs go up to 3500 or so nicely, after that revs will jump to about 4500 and the sound of the engine goes up accordingly to revs (but this happens in like 0,1 second). Then they will decrease down to 3600 and then normally increase again after that all the way up.

The car seems to be running normally otherwise, apart from the hole in boost.

Help - what could be the reason for this?


Thanks for the replies!

 

Get a new clutch

 

I can also be you TPS sensor sticking, has been that on two other Evo with VIII's that I know of. Or yes your clutch... Also search is engine is great on this site there have been many post on this..

 

sounds like your clutch is going

 

+1 on the clutch. it could also be (as mentioned already) the tps sensor sticking. you can check your clutch by doing a 4th/5th gear pull from around 2k wot. if the revs go up and the car doesnt go anywhere like it should then very well your clutch. good luck.

 

yup....clutch

 

I was doing exactly that - but as I wrote, it just bounces the revs for about 600-1200 up and then back down, so it's really just a bit of a slip, doesn't start spinning off. Car accelerates after that, just a second or so of lag before it does start accelerating properly again.

 

Clutch

 

Clutch

 

After some testing, it seems that it's not the clutch... Seems more like there could be something leaking turbo related. Cause it really slips only when you go from less than full to WOT. Even at 5000 revs it would still jump up, than go back down.

 

Take the car out and test it in top gear same revs. CLUTCH!

 

my stock clutch was doing this after 5,000 miles,i would upgrade to an exedy twin disc

 

Blew my clutch last week...same problem...