check the catalytic converter. mine went and resulted in a "quiet exhaust". dropping the down pipe to check the converter confirmed the issue. all fixed and boosting like new now.

 

[QUOTE=Evo8cy;11563741]Find a good crank position sensor and replace yours with it.

I replaced mine with a brand new genuine Mitsubishi one. Made no changes

 

[QUOTE=H8WRX;11563983]

Since you have done most of what could have been the cause of the issue, as you posted on this thread, including the above, then I would suggest getting an ecu from a friend, swap yours for his and see if it re-solves the problem.




I had a similar problem as yours at some point, and on mine, it was the power fc I am running, as I had to address the problem by fixing the ecu.








Marios

 

New findings- I had an electriction look over all my wiring etc and nothing came back bad, only thing we found was that when we gave the map sensor and the harness plug a wriggle, it would effect the cars idle and if we wriggle hard enough the car would stall and refuse to turn on. Also when unplugging the iat sensor on idle it does not effect anything and continues to idle normal.

 

Your map sensor should be the cause. Exactly what was wrong with my car just last week. Ordered a new omni 4 bar from Tom and it drives way better than what it used to. Maybe my map sensor was acting up but not enough to effect the fueling yet and then it just gave up. If I am correct Tom's tune doesn't require the iat reading. I'm still waiting for my tune from him. Glad you got this figured out.

 

Cheers mate, i will get a new MAP sensor and i can't confirm if he does or does not use the IAT but when i unplugged it she was normal but try driving with it unplugged, it turned to ****. so i would assume its working. Yeah Tom was the one who said they rarely go bad but it does happen. Good luck with your tune with Tom, he is a great tuner, knows what he is doing and you won't be disappointed.

 

Just wondering, with your map sensor being faulty, what issues did it cause you? misfiring? etc?

 

No misfire no code. I had just finished doing my head studs, installed my ported head from curt brown and also added a fp black this was all still on my stock turbo tune. I am still waiting on my tune with Tom but i drive my car once in awhile to make sure everything is okay and ready for Toms tune. Car drove fine but was lean when clutch starts to engage. I thought it was the tune. Then one day right after a hard pull, The car just hesitate and lost power. I pulled over to the side streets and car just dies. Then I was having a hard time restarting the car. I thought I blew a hose or something but everything was fine. When I got the car started, it idled fine. When I try to drive it it would just die. I was not too far from home, was able to get it home one block at a time by rolling most of the way. Then the next day I go start it and it drives fine (engine cooled down??). It's under boost when it starts acting up and I hurry home cause problem still there. I tried to replace the fuel pump as I have more than one walbro 255 at home, but that wasn't it. I made a post just like you and I researched how the fuel pump worked. I then tested voltage while cranking and know my fuel system is okay. A member told me to check the map sensor as his was faulty as well. I thought about it and it made sense as under boost that's when the ecm sends signal to the battery voltage relay to the fuel pump. It seemed like fuel pump was bad. The map was not reading the boosted conditions that's why the ecm didn't give signal for the battery voltage relay to kick on. Ordered it from Tom as I know he always have them in stock and he is pretty quick with parts. Pulled out the old one, made sure the tiny hole was not clogged and installed the new one. Car drove so much better. I knew right away it was the map sensor. That's why when I saw your post I told you right away check your map sensor. Electronics doesn't have a set time to go bad. When they do, you got no choice but to replace it.

 

Well I thank you good sir for your help, time and efforts. It sounds exactly like my problem. I ended up purchasing mine from stmtuned as I'm from New Zealand so shipping takes a long time and Tom is hard to get a hold of sometimes. I appreciate the time and effort you have given to explain your issue again for me. I can imagine you having to tell the story many times like I have when trying to locate the issue and having to repeat your self to others becomes more dull as you go. I am currently waiting for my new map sensor to arrive now. I have my fingers crossed super tight that this is the cause of the issue as I have consider everyone's ideas and ended up replacing alternator + belt, coils and plugs, crank and cam angle sensor just to have no results. I will keep this post updated when the map sensor arrives. Let's hope for the best

P.s, good luck with your tune by Tom, he will do a bloody good job and you won't be let down. Fp black plus ported head by porting king will equal good power

 

Thank You. Hope you get it fixed. Tom is pretty good when coming to ordering parts. He is actually very fast.

 

There once was a time when he replied fast for me but hasn't been for a long time lol.

 

Same thing happnd to me

 

And was the cause of your issue your map sensor?

 

UPDATE!- What an adventure! so much trial and error to find the cause of my issue but the end has finally come, the issue has been resolved. Map sensor is the winner. The new Map sensor arrived today, put it in straight away and took the Evo for a good 2 hour drive without the car dying or stalling. 2/4 issues have been fixed from the Map sensor. No more dying after driving a while or stalling when engaging clutch coming to a stop. 2 more issues remain but one step at a time. The car is still misfiring and the knock sensor light (check engine light) is still flashing around 5500rpm in 4th gear (very consistent, same rev range in the same gear). The knock never use to happen, but have had the issue for half a year now.

On the lines of misfire, i have changed all the spark plugs and coils. i notice when it does misfire, the AFR drops lean before going rich. It doesn't always misfire but majority of the time it will.

 

What gap did you have the spark plugs gapped at? What coil setup are you running? If oem coils did you replace the wires?