ClubCJ - The CJ Lancer Club

Hi guys,

I've bumped into this issue recently, after doing some researches across all the ralliart/evox forums, I can't seem to come to a solid conclusion as to what the issue might be.

So the car was running perfectly normal until I have hooked up an aftermarket catback exhaust myself whilst i had the car on stands. And went for a quick test run i noticed under constant throttle (same speed, same amount of throttle), the RPM will drop down by 200 and jump back up 200, it is more noticeable when going up hill. Idle is perfectly normal however.

Having this slight drop in RPM and bounce back up, the car kind of feel a bit jerky. I've narrowed down the following based on my research, and i was wondering if you guys can shed some lights and possibly have some 1st hand info to share?

- Initially thought it was the fuel pump relay (original pre 2010 black relay), salt shaker test indicated it went bad, bought a blue relay from RTR, it feels better, smoother, issue is slightly improved but still exist

- Possible leak due to a DIY job on installing the CBE?

- Checked the fuel pressure regulator line, all connected fine

- it happened (or came to my attention) after the CBE was installed, car was otherwise stock, no tune, stock intake. Could it play up with stock stun with CBE?!

- Lastly, I am steering towards possible clutch slip? Some from the US reported similar issue with RPM drop and bounce under acceleration, and indicated it might be the clutch slipping.

I was going to get a tune in April ish but looks like this will have to hold until i fix this issue. Any input or help will be much appreciated!

Thanks in advance.

unless u changed your cat i dont think a CBE will give u any ecu problems, it sounds like clutch slip moreso under load like uphill. but the fact that you say it drops 200 then goes back to normal says its not clutches.

thered be no slip at idle of course as the clutches are not under any load.
it could be something else though, even something as mundane as a faulty sparkplug or a clogged fuel filter.

personally i`d take it to mitsu for a fault diagnosis.

2 questions, do u get any CEL`s?
and how long since you`ve changed your transmission fluid?

check your Fuel pressure reg hoses, one of them could be loose.

Thanks for the input guys, much appreciated.

It hasn't thrown any CELs, and transmission fluid was not changed since my ownership 6months ago, I'd imagine it is well due for one, and as I've planned, I am getting the castrol transmax dual 20L drum when I head back from overseas in March, and will dump the fluid then.

I'd have this as a priority when I get back and make this the very first part of troubleshooting, if no help still, id send it in for a diagnosis.

But it is good to know it doesnt sound like a clutch slip.

I checked the FPR hose, all connected fine.

Thanks Alan!

replace tranny fluid and filter.
check fuel return hose, there is a good photo of its location on another thread.


if you find that the problem is worse after a fluid change then the issue is most definitely mechanical.

Also be sure to thoroughly inspect the drained fluid for large chunks and shards.

Even if you don't have any CEL's on the dash, i would suggest to run anyway a diagnostic, i had a spark plug faulty, no cel on the dash, but the rev was bouncing up and down in park and neutral, i run a diagnostic and found out the problem, cylinder 2 wasn't getting spark (can't remember the code).
Have you got any back fire from exhaust when you test drive it?

himynameisdaniel wrote:replace tranny fluid and filter. check fuel return hose, there is a good photo of its location on another thread. if you find that the problem is worse after a fluid change then the issue is most definitely mechanical. Also be sure to thoroughly inspect the drained fluid for large chunks and shards.

Thanks, that will be the first thing to do when I head back, fingers cross its just the fluids

SEB15 wrote:Even if you dont have any CELs on the dash, i would suggest to run anyway a diagnostic, i had a spark plug faulty, no cel on the dash, but the rev was bouncing up and down in park and neutral, i run a diagnostic and found out the problem, cylinder 2 wasnt getting spark (cant remember the code). Have you got any back fire from exhaust when you test drive it?

Did it manage to pickup the code even without the CEL?
I have a bluetooth obd2 will have a crack at that tomorrow!

Thanks mate

Not all codes will register a CEL.
Some have thresholds

Hi Bernz,

When you say the revs drop off 200 then come back, does it do it like it's rev hunting?

See video of issue I had recently in my RA:

http://youtu.be/9y66sU3K6eE

If it's anything like mine, my clutch/mechtronics was gone. Mitsu replaced both under warranty and she's back to normal.

It would only really happen to me when i was doing a constant speed in 5th, then the change up to 6th was really jerky for lack of a better term

Hi Bob,

Yes it does the same thing, it only does that when I apply throttle and it seems to happen across all gears!

That's no good sign LOL clutch will cost a fair bit to replace without warranty!

SEB15 wrote:Even if you dont have any CELs on the dash, i would suggest to run anyway a diagnostic, i had a spark plug faulty, no cel on the dash, but the rev was bouncing up and down in park and neutral, i run a diagnostic and found out the problem, cylinder 2 wasnt getting spark (cant remember the code). Have you got any back fire from exhaust when you test drive it?

Yes I did get back fire AFTER installing the CBE, in fact I still get a lot when I let go and reapply gas.

I just feel like it has something to do with the CBE, as the car was running fine prior to the CBE being put in, and that night after I put on the CBE, it started happening from the test drive.

Bernz wrote:Hi Bob, Yes it does the same thing, it only does that when I apply throttle and it seems to happen across all gears! Thats no good sign LOL clutch will cost a fair bit to replace without warranty!

I really hope it's not the same issue then man! You're not gonna want to hear this but when I got the paperwork for the work done on mine - it was about $4,400+ from memory! ouch

Bernz wrote: Yes I did get back fire AFTER installing the CBE, in fact I still get a lot when I let go and reapply gas. I just feel like it has something to do with the CBE, as the car was running fine prior to the CBE being put in, and that night after I put on the CBE, it started happening from the test drive.

In that case you might have dramas with the O2, wired thing is not trowing CEL on the dash tho... Have you run a diagnostic yet? ODB2 and a mobile ph will be just fine. i use Torque app, works well

I have the same issue and it has gotten progressively worse will be taking it to Mitsubishi in a few weeks.

My car is also 2010 model can you send me a copy of the invoice with the part numbers thanks as I believe that Mitsubishi have upgraded the clutch packs some time during 2014 which means its a known issue that should be covered by warranty.

If anyone wants replacement clutches you can get OEM Evo x online for about 750 dollars and the labour and fluids to install i've been quoted is around $1500