RPM rises 400 when doing 3 to 4 shift [MERGE]
well its not my bov, i tried the stockone...still done it, unhooked the XEDE, still done it on stock ECU, i dont know what else it could be...i noticed my throttle cable is a little loose, but i dont think that would be it, can anyone please help me on this, its really starting to bother me.
My Evo has started doing this, although my symptoms are slightly different. I noticed about a week back that when I'm coming off a hard pull in 4th gear, shifting into 5th grinds every time. Turns out that when I shift, the RPMs keep climbing ~500rpm, which in turn must be throwing off the synchros, because if I wait for the RPMs to drop before I shift, then it shifts fine. Doesn't happen in any of the other gears though...
Question to the folks that are having this problem: Are you running the stock IC piping and hoses?
My theory right now is that perhaps the ballooning of the stock IC hoses is causing the throttle body to stay open/close slower than it should. I've noticed that 4th (and 5th) gear seem to run slightly higher PSI on my car than the lower gears.
l8r)
Question to the folks that are having this problem: Are you running the stock IC piping and hoses?
My theory right now is that perhaps the ballooning of the stock IC hoses is causing the throttle body to stay open/close slower than it should. I've noticed that 4th (and 5th) gear seem to run slightly higher PSI on my car than the lower gears.
l8r)
Hi guys,
Just read through this long post since I started to get this problem as well. I’m definitely not imagining this since a friend of mine who works at
here in Sweden test drove the car and immediately noticed it as well. The symptom in my car is that it happens on high boost and high rpms only. Thing is that I’ve had lots of other problems with my turbo kit and stuff and I have changed lots of things since my last proper tuning so I don’t know if a new tuning would maybe solve this some how.
In my car I need to rev past 5k-6k and be at WOT for this to occur. What happens is that if I let go of the accelerator at say 5,5k and press down the clutch revs could go up to maybe 6k before starting to fall down. Most noticeable in low gears, 1st to 2nd and 2nd to 3rd. Just as if you didn’t release the accelerator properly before shifting. I’m not convinced that it could be due to the clutch not releasing because how could that increase the rpm? Only way to increase the rpm mechanically is to down shift but that has never been the issue here as far as I know?
But what confuses me is that to be able to rev the engine to 6k you need quite a lot of air going into the engine don’t you? Could the engine actually rev to 6k if the throttle is totally shut?
I also suspected my BOV to start with, I also cleaned it and oiled it up but that didn’t seam to make any noticeable difference, it’s an HKS SSQV vent to atmosphere btw. I have noticed a similar thing before, there was some kind of filter included with the HKS BOV that was supposed to be installed on the hose to the BOV. This filter cracked in half but didn’t fall apart and among other strange things caused by that was something similar to the problems described above. That’s why I immediately suspected the BOV as the cause, on the other hand I’m not sure if the broken filter caused air to enter the engine through the hose or that the lack of a functional BOV caused it, or something else?
Just read through this long post since I started to get this problem as well. I’m definitely not imagining this since a friend of mine who works at
here in Sweden test drove the car and immediately noticed it as well. The symptom in my car is that it happens on high boost and high rpms only. Thing is that I’ve had lots of other problems with my turbo kit and stuff and I have changed lots of things since my last proper tuning so I don’t know if a new tuning would maybe solve this some how.In my car I need to rev past 5k-6k and be at WOT for this to occur. What happens is that if I let go of the accelerator at say 5,5k and press down the clutch revs could go up to maybe 6k before starting to fall down. Most noticeable in low gears, 1st to 2nd and 2nd to 3rd. Just as if you didn’t release the accelerator properly before shifting. I’m not convinced that it could be due to the clutch not releasing because how could that increase the rpm? Only way to increase the rpm mechanically is to down shift but that has never been the issue here as far as I know?
But what confuses me is that to be able to rev the engine to 6k you need quite a lot of air going into the engine don’t you? Could the engine actually rev to 6k if the throttle is totally shut?
I also suspected my BOV to start with, I also cleaned it and oiled it up but that didn’t seam to make any noticeable difference, it’s an HKS SSQV vent to atmosphere btw. I have noticed a similar thing before, there was some kind of filter included with the HKS BOV that was supposed to be installed on the hose to the BOV. This filter cracked in half but didn’t fall apart and among other strange things caused by that was something similar to the problems described above. That’s why I immediately suspected the BOV as the cause, on the other hand I’m not sure if the broken filter caused air to enter the engine through the hose or that the lack of a functional BOV caused it, or something else?
Last edited by EVOVII_SWE; Oct 20, 2004 at 07:19 AM.
I notice the same thing with the stock clutch when shifting fast at high rpm. Looks like the rpm does not drop and the time you go from 2nd to 3rd is very short. I thought it was my clutch slipping. Glad to see I'm not the only one. Never seen this happening on the honda,supra, and 911 that I've driven or test drive before.
This is my 1st MIT and AWD car but this doesn't sound normal.
This is my 1st MIT and AWD car but this doesn't sound normal.
Originally Posted by EVOVII_SWE
Hi guys,
Just read through this long post since I started to get this problem as well. I’m definitely not imagining this since a friend of mine who works at here in Sweden test drove the car and immediately noticed it as well. The symptom in my car is that it happens on high boost and high rpms only. Thing is that I’ve had lots of other problems with my turbo kit and stuff and I have changed lots of things since my last proper tuning so I don’t know if a new tuning would maybe solve this some how.
In my car I need to rev past 5k-6k and be at WOT for this to occur. What happens is that if I let go of the accelerator at say 5,5k and press down the clutch revs could go up to maybe 6k before starting to fall down. Most noticeable in low gears, 1st to 2nd and 2nd to 3rd. Just as if you didn’t release the accelerator properly before shifting. I’m not convinced that it could be due to the clutch not releasing because how could that increase the rpm? Only way to increase the rpm mechanically is to down shift but that has never been the issue here as far as I know?
But what confuses me is that to be able to rev the engine to 6k you need quite a lot of air going into the engine don’t you? Could the engine actually rev to 6k if the throttle is totally shut?
I also suspected my BOV to start with, I also cleaned it and oiled it up but that didn’t seam to make any noticeable difference, it’s an HKS SSQV vent to atmosphere btw. I have noticed a similar thing before, there was some kind of filter included with the HKS BOV that was supposed to be installed on the hose to the BOV. This filter cracked in half but didn’t fall apart and among other strange things caused by that was something similar to the problems described above. That’s why I immediately suspected the BOV as the cause, on the other hand I’m not sure if the broken filter caused air to enter the engine through the hose or that the lack of a functional BOV caused it, or something else?
Just read through this long post since I started to get this problem as well. I’m definitely not imagining this since a friend of mine who works at
here in Sweden test drove the car and immediately noticed it as well. The symptom in my car is that it happens on high boost and high rpms only. Thing is that I’ve had lots of other problems with my turbo kit and stuff and I have changed lots of things since my last proper tuning so I don’t know if a new tuning would maybe solve this some how.In my car I need to rev past 5k-6k and be at WOT for this to occur. What happens is that if I let go of the accelerator at say 5,5k and press down the clutch revs could go up to maybe 6k before starting to fall down. Most noticeable in low gears, 1st to 2nd and 2nd to 3rd. Just as if you didn’t release the accelerator properly before shifting. I’m not convinced that it could be due to the clutch not releasing because how could that increase the rpm? Only way to increase the rpm mechanically is to down shift but that has never been the issue here as far as I know?
But what confuses me is that to be able to rev the engine to 6k you need quite a lot of air going into the engine don’t you? Could the engine actually rev to 6k if the throttle is totally shut?
I also suspected my BOV to start with, I also cleaned it and oiled it up but that didn’t seam to make any noticeable difference, it’s an HKS SSQV vent to atmosphere btw. I have noticed a similar thing before, there was some kind of filter included with the HKS BOV that was supposed to be installed on the hose to the BOV. This filter cracked in half but didn’t fall apart and among other strange things caused by that was something similar to the problems described above. That’s why I immediately suspected the BOV as the cause, on the other hand I’m not sure if the broken filter caused air to enter the engine through the hose or that the lack of a functional BOV caused it, or something else?
Exactly, I have put the stock BOV back on, that didnt help...still did it. I hooked up the ECU back by itself without the XEDE, that didnt help...still did it. So i have pretty much ruled out it being the XEDE or the BOV, i dont really see how it could be clutch related either, but the problem just started about 2 weeks of having the XEDE.
Evolving Member
Joined: Oct 2002
Posts: 362
Likes: 0
From: Northern Michigan
I've had this problem since I got my Evo early last year. I only really notice it during HPDE events on a race track. Last weekend, I was at Road America and it was particularly annoying. The drivetrain on my car is stock except for a full 3 inch exhaust system.
The severity of the problem seems to vary from time to time. It seems worst in cold weather when the air is denser and the engine is pumping more air mass. At the moment, my theory is that it is the throttle plate not closing fast enough under high boost/rpm conditions - for whatever reason, the air flow through the throttle body is keeping the plate open longer than it should. I'm going to try installing a supplementary spring this weekend to put more closing force on the throttle plate and see if that helps.
The severity of the problem seems to vary from time to time. It seems worst in cold weather when the air is denser and the engine is pumping more air mass. At the moment, my theory is that it is the throttle plate not closing fast enough under high boost/rpm conditions - for whatever reason, the air flow through the throttle body is keeping the plate open longer than it should. I'm going to try installing a supplementary spring this weekend to put more closing force on the throttle plate and see if that helps.
Originally Posted by tsi90awd
I've had this problem since I got my Evo early last year. I only really notice it during HPDE events on a race track. Last weekend, I was at Road America and it was particularly annoying. The drivetrain on my car is stock except for a full 3 inch exhaust system.
The severity of the problem seems to vary from time to time. It seems worst in cold weather when the air is denser and the engine is pumping more air mass. At the moment, my theory is that it is the throttle plate not closing fast enough under high boost/rpm conditions - for whatever reason, the air flow through the throttle body is keeping the plate open longer than it should. I'm going to try installing a supplementary spring this weekend to put more closing force on the throttle plate and see if that helps.
The severity of the problem seems to vary from time to time. It seems worst in cold weather when the air is denser and the engine is pumping more air mass. At the moment, my theory is that it is the throttle plate not closing fast enough under high boost/rpm conditions - for whatever reason, the air flow through the throttle body is keeping the plate open longer than it should. I'm going to try installing a supplementary spring this weekend to put more closing force on the throttle plate and see if that helps.
Originally Posted by EVOVII_SWE
But what confuses me is that to be able to rev the engine to 6k you need quite a lot of air going into the engine don’t you? Could the engine actually rev to 6k if the throttle is totally shut?
Newbie
Joined: Oct 2004
Posts: 10
Likes: 0
From: Knoxville, TN
Originally Posted by tsi90awd
I'm going to try installing a supplementary spring this weekend to put more closing force on the throttle plate and see if that helps.
Newbie
Joined: Oct 2004
Posts: 10
Likes: 0
From: Knoxville, TN
Originally Posted by 93civEJ1
Dont know, Tell me how this works out for you guys, but it just seems kind of odd that maybe 10 out of the few thousand evo's around only have this prob.
Actually, I wonder how many people have posted "5th gear grind issues", when in reality it's not so much the 5th gear synchros grinding, but the RPMs rising that is causing the grind. The 5th gear issue is well documented by a lot of people.
l8r)
l8r)