Mitsubishi Lancer Evolution Forum banner

RPM problems

6608 Views 12 Replies 6 Participants Last post by  cobalt1060
2008 GSR
I have been having an issue with my rpm while driving and I can't figure out what the problem is. About a week ago I took my car to the local dealership and they did and turbo D service and an ecu reflash which fixed one problem but seemed to create another. When I'm driving along (on the highway it is more noticeable) and slowly accelerate the rpm bounce just a little bit and the car feels like its sort of jerking a bit. It is most noticeable when i'm doing 90km/hr (55mph) and slowly accelerate to 110km/hr (68mph) and I'm in 5th gear. I've noticed it while accelerating in 3rd and 4th as well and it only happens between 2500-3500rpm.
I took it to the same dealership today that did the ecu reflash last week and the took it for a test drive and said they couldn't replicate the problem but were unwilling to take it up to 100km/hr due to 'road conditions'. The roads aren't really that bad today so it seems like an excuse because they don't want to find the problem for some reason. They said that I could be running too many electronics, the only thing i have is an HID conversion kit and then they also said it seems like from what I'm saying it might be my spark plugs but I changed those out a month ago. Then they said that I might not be warming it up enough before I start driving, I let it warm up for at least 20 minutes before I move it. In the end they said that unless there is an error code they have no idea what it might be and to just keep driving it and if it gets worse to bring it back. I know something is wrong and I really want to figure out what the problem is. Does anyone have any ideas what this could be? I checked the Vacuum line for fuel pressure regulator and it is connected so thats not the problem. The only thing I've changed on the car since I got it was putting on a turbosmart BOV, is it possible this could be the problem? I uploaded the video to youtube and if you watch it near the end when I reach about 3200rpm it is most noticeable, it doesn't look like much but it is very noticable when I'm driving.
See less See more
1 - 1 of 13 Posts
The video doesn't look like the classic rpm rise followed by drop that you see when the clutch slips. Seems more like something is not quite running right. Do you have any mods? Also, I'd get under the hood and check your FPR vacuum hose to make sure it didn't pop off.

Quick clutch test:
while crusing in 5th at highway speed, give it a good amount of gas and watch the rpms. If you see a rise followed by a drop and then a steady increase as you gain speed, the clutch is slipping just while you're building boost.
1 - 1 of 13 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.