Hey guys i live in buffalo and its winter obviously. A couple times this winter when id start my evo the car would stuuder over itself and die. I can immediately start it back up and its fine then. Well recently when i am driving car and drop into neutral and coming to a stop the car dies. No CEL but then starts right up again, only when i go into neutral. I hve a injen intake, turbo back exhaust, and a cobb accessport stage 2. The fr hose is connected i checked that. Also i monitored my afrs at idle and they read 10.5-11.1 and my boost pressure was -9 - -8.9 at idle. Idk what that converts to to vaccum. Anyone help? Im at a loss

 

Are you tuned? Mods?

 

I listed everything. A injen cold air intake, and a turbo back exhaust and im tuned with cobb accessport stage 2. Cars been fine for like a month and a half. I check my IC couplers and they very tight. Idk what else to look for

 

Lol, where did you list everything? I would try to check the BCS as well. Don't know if that can affect idle AFRs

 

I dont think the boost control solenoid would do that. Any other options?

 

ok.. so here is what I took from your post... your car has an intake, turbo back exhaust and a COBB AP with a OTS tune... ( please correct me if i am wrong..)

your car symptoms are as of right now NOT consistant, i.e. each and every time this happens.. it is intermitant ( i cant spell today )

symptoms:
car stutters after being started and runs at an AFR of 10:5-11:1.
when cat goes into neutral at a STOP the car dies, or hesitates.


questions for you:
1.) does this happen at EVERY start, or only COLD start.( the starting issue)
2.) what injectors are you using
3.) When did you install your intake... did this happen AFTER installing the intake?
4.) What map are you using?
5.) What temperature is this happening at.


from what i can tell, atleast for me I would start at the MAF. common symptoms such as poor idle, high idle then low idle and irratic idle. also starting then shutting down right after or comming to a stop sign points to a MAF, or boost leak. either way the car isnt getting either the air it needs, or the signal isnt telling the ecu that it is getting enough air/fuel

when the maf isnt hooked up, and you start the car.. it should go pig rich.. i.e. 10.5-11.1 but in that same hand that is part of the tune... rich at startup to help accelerate the warm up process.

start looking there... and check all your vacuum lines again... see if you can make a log..

 

I believe that MAF sensors only flow a certain direction, that's how my Mustang was anyway. Could be another simple thing to check.

 

hey guys i did a log. The car acts completely fine now that i filled up the gas tank. The numbers look good i drive it like a baby, but i was still able to pull 20 punds of boost no problem. As you will see too even at 20 pnds of boost im at a perfect afr. I have no knock and the maf voltage looks good. But look down at the lower rpms my afrs are so so so rich. ANy suggestions or can someone shine a light on this for me?

 

Let me know what u guys think

 

If I remember right around -10 psi is about -20 in Hg so that's about right. Your car is probably adding air to try and idle with all that fuel, that's why you're around -9 -8 at idle. That is pretty rich for idle and part throttle, probably runs like a dog.

You said you have the Cobb AccessPort, is it their tune or someone else's? Cobb is pretty reputable so I'm sure they tuned all areas of the map and adjusted tables for weather. Not every tuner does that though. Most just tune WOT to give you a nice number and leave the rest all crappy.

If it's all of sudden or inconsistent then it's typically electronic and something simple, just gotta find it. If you did get the tune from Cobb I'd call them, they might be able to find a solution faster and help troubleshoot. That's why you paid them the big bucks

 

definitely would look into getting a pro tune it makes a difference
also your running slightly lean under full boost

 

Yes i bought a brand new cobb accessport. Downloaded the maps and uploaded them. I have no idea what it can be. Anyone have any suggestions as to where i should look first. Maybe my maf is dirty? I have no idea and the worse part is im throwing no codes

 

big boost leaks cause rich idle conditions and also cause stalling.

 

Thats what i figured. But i dont hear or see any leaks that would be big. I will be smoking the engine bay later to see. Anywhere specific you guys would reccomend to look?