Hey everyone, I have a 2006 Evo MR. It's e85 tuned, it has 1400cc injectors, cosworth m3 cams, stage 2 clutch and a bunch of other mods I can list off if necessary. All the tuning has been done by a professional tune shop.

It all started after I changed my battery, not sure if this is relevant or not, but when I started my car after work the next day the rpms went up to 2k then started dropping down until the car stalled out. I had to rev it to keep it on and eventually it went back to normal. It was acting like it was on the wrong map (91 instead of e85) but it wasn't. It's been doing this every cold start since (3 days). I thought it was the MAF or ECU at first but it's not throwing a code. It has a stock ECU that's been tuned. And this only happens during a cold start.

Then I noticed surging in between gears and it does not drive well up hills. What really made me concerned though was when I was in 5th or 6th gear at around 70% throttle and a full load of boost the front of the car starts to violently shake until I release the gas.

I have used the search function and I see most people said the shaking is from the clutch which would make sense, but I haven't seen anyone mention the idle problem along with it.

Does anyone know if this is all related or what?

 

On a dual map tune when the battery is disconnected the Evo will switch to the default map. Most Evos have their default map set to the 91 map. If you are 100 percent sure that the map is correct then you might have a major boost leak or a missing electrical connection.

For now I suggest not driving the Evo at WOT (wide open throttle). If you have some time this weekend I can take a look and do a boost leak test to narrow down the issues.

Also another issue could be you got a bad batch of E85. Its rare for that to happen but it could cause issues like this.

 

I'm definitely sure that it's on e85 because I switched it back after I changed the battery. The first time it didn't the stalling out thing I turned the car off and made sure it was on the right map and it still did it.

I should be free this weekend. I might bring it to fftec on Thursday because it's been giving me anxiety not knowing what it is and they're the ones that did the tune.

You think every thing is related though?

 

You are in good hands if you take it to FFtec. They will be able to tell you what's going on with the Evo. Hopefully its a small issue.

Sometimes small problems can cause big changes in the drivability and in other cases you can catch them before they turn into big problems. There are few things that can be diagnosed from my arm chair most of the time its when I start working on it that I find out the real issue.

 

Where did you get your Evo tuned?

 

It'll also erase your STFT and LTFT which can effect idle and cruise. They should learn themselves again fairly quickly though.

 

FFtec was my last tuner. They did a touch up tune which was done about three years ago.

I forgot to mention that you will want to stay out of boost if your Evo is acting weird. Just use vacuum or 0-5 psi to drive around.

 

Any update on this?