EVOX84

All,
I have looked around the forum and read the posts/threads on idle issues however, they are all about 2yrs old so i would like to start a new one for some updated info/Ideas...

Here is what I have going on:
Car - 2015 MR with less than 6K on the car
Mods - UR Catback dual tip.
Issue 1- The car seems to jump around a bit at idle and by this i mean that the car jumps between 700ish RPMs and 900ish RPMs. It does this after its warmed up.
Issue 2 - The car sometimes drops the RPMs to around 500 when i give it gas from a stop.
Issue 3 - The car sometimes feels like this is hesitating at higher RPMs

I have never seen any codes on the car nor any warning lights. I only put shell 93 gas in her and the air filter looks a little dirty but not to the point where i would replace it. I have looked at all the vac lines and zip tied the fuel vac line by the dipstick. Not too sure where to go from here other than the dealer.... I know there was a reflash for older EVO Xs that had what seemed to be the same issues but i haven't seen anything out there for newer ones needing or getting that reflash. Anyways, thanks for your input!

Bhsj13

you need a tune.....? maybe?

yifuqiao

iTrader: (4)

My 2014 GSR had similar "issue". It never bothered me. It never stalled or anything like that. But a aftermarket tune did fix that.

e_kobz

iTrader: (36)

My Evo X had a similar issue when I swapped intakes. When it was stock the idle was rock solid. Then I had a AEM intake box. The box changed the MAF housing so it made idle a little crazy. 1100rpm then drop to 500rpm. Then bounce up and down, then stay at 700. I ended up selling the AEM intake box for a ETS intake. This helped the issue because the ETS intake retained the oem MAF housing. Still had a little idle bounce, but not as bad as the AEM. Once I got it tuned I never had a issue again.

My advice is get a tune. It does wonders on the Evo X. It's the single most important mod you can do to your car

EVOX84

The car is still under the warranty so I'm not really looking to void that just yet. However I will agree that a tune would iron out alot of issues with the stock map that is on the ECU. Just thought I would see if anyone had any ideas or thought of something i may have yet to check on the car. I'm thinking that the next thing to do is change the air filter and see if that helps.

Napalm_Enema

You can't add parts without a proper tune, and expect it to run well. If you're not going to tune it, get those parts off of it and leave it 100% stock imo. I have a 2014 MR and it is still stock for now, and never has the issue you describe. I do have a drop in filter, but that doesn't require a tune, and smoothed out some of the pulling.

Doesn't seem like you should be running oddly with a CBE exhaust however. That shouldn't need a tune.

EVOX84

I agree with everything you are saying and i have built a number of big turbo V8s with a few people i know so i get how stuff works. My MR is bone stock outside of the CBE on the factory tune so i just dont get why it would be having any issues like that, so thats why i put this up here.. I know the old X's had a recall for some of the relays and a ecu reflash so i was just seeing if anyone has had to do this with the new ones yet.. Maybe Mistu put some old stuff off the shelf while building these last few evos... Joking, but i have seen this happen before with outgoing cars.

Anyways takes for your feedback and good to know about the drop in filter b/c i have been thinking about that myself.

Napalm_Enema

I got the Cosworth filter because it doesn't need oil. Car feels much better with that. I do want to say I got a few ECU reflashes when I bought my car, not sure if you should already have those or not but worth checking.

Your car should be dead smooth pretty much imo.

EVOX84

What year is yours?

Napalm_Enema

2014 mr

Of note I still feel dead spots when in high RPM's ripping through gears. I think that is a drawback to the tune.

I'm getting some boltons and tune done next week, will share impressions but I am thinking the car will be all new with almost 100 extra hp and tq.

Can't wait!