i put on a front mount like 2 months ago. it ran fine until after a week of driving when it would suddenly stall out or idle really low. for example, if i am driving and throw it into neutral itll hit 0 rpm then bounce up to 750 rpm most of the time but a few occurrences it has stalled on me while driving! sometimes it decides to idle below 750rpm like around 600 or so it seems. also, if i have the clutch in with 1st gear engaged, if i give it throttle it will want to stall out unless i constantly give it gas. my temporary solution has been to reset the ecu which gives me about a week of normal idle behavior until it happens again.

i did some wot pulls and heard a leak so i went over all my fmic couplings and made sure they were TIGHT and the sound went away. however, the problem still occurs

the relevant mods on my car are:
2004 subaru wrx
catless turboback
catless uppipe
turboxs short ram intake
stock turbo
stock bpv
ssac fmic
xpt tuning stage 2 OPENSOURCE ecu map. this map is meant for a large TMIC but i dont see how a fmic would cause this

thats about it performance wise.

ive narrowed it down to several things:

1) leak - double checked for leaks as mentioned earlier. from a hearing stand point i dont hear anything but i think the next thing i will do is a boost leak test...

2) dirty maf sensor/intake filter - cleaned it, made no difference

3) dirty IACV (idle air control valve) sensor - cleaned it, made no difference

4) needs tuning - possibly? but i know several people who run stock turbos untuned with a FMIC and dont have this issue.

5) too lean at idle - ive attached some logs with AFRs and other relevant data for you to see.

wrx at idle:
http://spreadsheets.google.com/ccc?k...zxb_KtUg&hl=en

wrx with a few blips of the throttle to show the idle dropping down to 400 rpms:
http://spreadsheets.google.com/ccc?k...45hy8FTw&hl=en

im honestly lost here. any insight would be appreciated.

alan

 

From the logs it looks like you have a bad/unplugged IAT sensor unless its 160 degrees outside.

 

Check connection/replace your IAT sensor.
Also you should get a professional dyno tune done since it is
a safe precaution to after installing a FMIC and it could be
the source of your problem.Just because one person didn't
need a tune after a FMIC doesn't mean you don't.

 

the logs are right after i did a 45 min drive/

does that help or are those IATs too high still?

 

Unless its close to 160 outside, which i highly doubt it is, the iat shouldn't be reading that much above ambient(outside temperature).

 

one, u dont need a FMIC...

two, running one without a tune for it wont help..

three, the more piping u have the more likely there is a leak of some sort...

four, would recommend just taking it to a shop that will figure out the problem, and then get it tuned!