Hey so my car is an 06 Evo 9 running speed density with a 4 bar map sensor. Its a 6262, built motor. Spoolinup COP. Fic2150cc stock ecu, ecuflash evoscan tactrix 2.0 cable (i have but dont really know how to work) also Tephra patch, i think thats what its called lol.


So i was driving it in the morning everything was normal. On my way home from work i stopped to get gas, filled up 93, my car started up normal and felt normal. About 3/4 of a mile down the road im getting onto the highway and im noticing my car is having a little quick sputter or misfire then be fine, then it happens again a mile or so down the highway, and goes away. The longer i am driving the more frequent and worse it got. So now about 10 miles down the highway its starting to get really bad. lt kinda feels like the ignition was cutting out. At times it felt like the pedal wasnt doing anything as i was pressing it down then a second or 2 later it will just jerk back into power pretty rough. By the time i made it home i was barley able to go more than 40mph. I immediately thought i just filled up with bad gas so i drained my tank and put fresh 93 from my local gas station i always go to. Now the next day i go to test my car and she starts right up and feels back to normal as i head for the highway again. As im getting on the highway it starts to do the exact same thing. A quick little sputter/misfire every once and a while, to misfiring pretty bad feeling like the ignition was cutting out. luckily i was able to turn around and make it back home all within a 3-4 mile loop. i have a wideband on my car and when its not cutting out everything looks normal and as soon as it cuts out and jerks the a/fs go all over from lean to rich and back and fourth. As im pulling down my street my car isnt even holding idle its just stalling right out. If i start it and hold the gas down to the floor it wont go higher than 3-3500 rpms and drops and it sounds exactly like the stock launch control. the net day it starts right up feels normal but before i can even make it down my road all of the symptoms came back so i only made it a couple of blocks from my house and it shut off. Now it doesnt start at all. it cranks but doesnt do anything else. Still no check engine light which is really driving me crazy . I tried a new 4 bar map sensor and a new crank sensor and nothing changed at all it still doesnt even try to start. i pulled my plugs and checked if they had spark while trying to start my car and they are all sparking as its cranking so i have no clue as to what is wrong with my car. If anyone has any suggestions or advice or any ways i can check any other sensors that could be causing this problem? Thank you all very much for your time if you read this any help or advice is greatly appreciated. Thanks again!

 

Fresh tank of 93 and 2150 injectors?

sure the thing isnt just really rich and fouling the plugs?

 

Check your TP sensor if it is reading correctly or not loose.
If all good and still the problem persists.
Take to a reputable shop for diagnosis.

 

So this car has been my daily driver for the past year i have been driving it every day with no problems at all and i havent touched or changed anything either. When i hook up my thinkobd 100 it does show the tps % and its 0 when i dont press the gas 100 when its floored and 50 at half throttle so it does seem like its working accurate.

 

I also tried new spark plugs too and that didnt make a difference either.

 

So another weird thing i found today, when my key is in the ignition turned on (engine not on obviously lol) my IAC valve starts to get hot, really hot! After a couple mins it is almost too hot to touch. I took out the IAC valve and turned the ignition from off to on for a sec then back off and back on again to test if it cycles through its motions and it seems to be working but it does make a lot of noise.
Here is a video of it.

 

Here is a test to see if my spark plugs are getting any spark on startup and they also look like they are good.

 

And the last thing i checked was to see if the fuel rail is getting any fuel and the fpr gauge is reading good.
Another video with that.
This is a video of me actually trying to start my car. This is all it ever does now...

 

Did your ever fix the issue? Im having similar issues

 

Not sure if you still monitor this thread but I had a similar issue. Turned out to be my MAP sensor, and there was a break in the ground wire in the MAP harness. Swapped sensors, fixed the break in the line, car runs great again.