hey guys my 03 evo has been down for 3 weeks i drove it one day and the next it wont stay running. the symptoms are it will start then lean out and die, it wil only stay running if u heavly feather the throttle and then its stilll lean. its nothing in the tune i have had the tune in my car for 5 months and haven't had a problem.

i have changed the
cam shaft sensors
the crank sensors
cheak the timing its spot on
spark plugs
pig tails on injectors
the fuel pump is pumping fuel through the rail and the lines.


if anyone has had this problem please help im at the end of my rope.
i would be greatly appreciative.

 

Have you checked all the piping from the ic and making sure they are tight?

 

Can you log the O2 sensor or otherwise rule it out?

 

yes everything is tight i double cheaked and ran a boost leak test.

 

the o2feed back is low 10s and high 15s, 02 sensor is reading 0

 

Anyone?

 

did you ever fix this issue?
Im having this same issue and ive found 10 or so threads with people with this issue but no one has ever posted what the fix was.

anybody know?

 

I don't know. However, I would suggest checking fuel pressure. It sounds like a pump problem to me.

 

Have fuel pressure gauge in the car. Steady fuel pressure at 40 even when it goes lean.

Once the car gets through its episode, It will run fine, even at wot

 

Have you fixed the problem yet? I was having a similar problem during initial start up of my 03 VIII. Turned out to be an IAC issue. Could be the stepper motor itself is bad (it's easy to check to see) or the gasket around it is bad. I put some RTV on the gasket to fix it until I get a new one in. $12 shipped from STM for gasket and around $350 for the IAC but you can find it on amazon for around $50

 

EDIT...Just noticed this is from 2012.....I'm sure he's fixed it by now or sold his evo..LOL.

If it turns out to be your IAC, pick up a newer year IAC on here or Amazon like the other member suggested. You'll see the spring on the outside...more durable than the the one you are replacing.

2 and 3 are the ones I'm referring to. 4 is for your year evo. This is an old pic...not mine.

 

Thanks for the info! Picked up some replacements from a friend of mine who deals in Evos. Gonna try them out

 

so... ive figured out if i hold the throttle down just a bit, and hold the r's around 2000 rpm, the car will warm up fine.

more to come.