BOV Tuning/Rough Idle?

[jonseclipsegs]

I've been having some problems tuning my 1996 talon tsi awd. It has:
NEW MOTOR FROM MITSUBISHI
NEW HEAD FROM MITSUBISHI
Competition Street 2500 LB. Stage 1 Clutch -
K & N 4.5" Air Filter
Buschur Big 16g Turbo
Apexi S-AFC Super Air Flow Converter
Apexi AVC-R Actuator Valve Controller
Greddy Turbo Timer
Greddy Blow Off Valve Type S
Greddy Front Mount Intercooler
Greddy Front Mount Intercooler Piping
Fluidyne Radiator
3" Catback Exhaust System
Injen Intake Pipe
(boosting about 15psi)

I'm not that experienced with dsm's but my blow off has a big flutter to it, along with being fairly quite. It doesnt really have the high pitch "pffff" that I though was common. Its currently only has about one thread exposed. Im not sure if thats expected but I wanted somebody to post or pm me the Greddy Type S BOV stock instructions, or an answer on how I should tune this. Also, I have a very rough idling during all times Im in neutral. It will start and idle like its sputtering a little like its gonna stall, then if you drive it or rev it...it will drop to like 200-300rpms like its gonna stall then slowly come back up to like 900rpms. It runs and drives perfect other than this and it never has actually stalled out on me, but Im still concerned. Any suggestions or advice would be appreciated. Thanks.

 

[TurBoGs-T]

From the sound of the bov you may have it too tight for the amount of boost you are running. Have you messed with that SAFC because the sputter sounds like you are running rich.

 

[jonseclipsegs]

How much do you think I should turn the bov towards soft?? I'm not sure of the specifics of the safc (not experienced) but its the same as when I got the car. All I know is that the air fuel gauge jumps like crazy from rich to lean when I idle. What would be the best fix to that??

 

[4G63 GST]

its a common problem when trying to vent you bov into the atmosphere that the car will act in the way you described, extreme changing rpms and such and almost stalling ect. this is the cause for most people running the stock 1g bov to crush it. Tightening the spring tension inside the bov will mostly eliminate all of this problem once in for all. Other possible things that also work in conjunction with this is to obviously play with your tuning as well as get a different flapper for your turbo.

when tightening or crushing a bov it sometimes takes a little bit to notice the difference afterwards , due to the fact that your car has to adapt to the new change and teach it self how to use it .. (in third grader terms )

anyway .. i crushed mine and had no problems since.. !


Luke

 

[boostedinaz]

its a common...... ..........anyway .. i crushed mine and had no problems since.. !


Luke

He has a Greddy so what does cruchins a 1G BOV have to do with anything???


Are you venting the BOV or not. That will help with a diagnoses.

Michael

 

[jonseclipsegs]

like i said...im a newber and i bought this car because it was a deal that couldnt pass up. so how do i know if i am venting to atmosphere or not?? Either way, how do i tune the bov to get positive results?

 

[boostedinaz]

like i said...im a newber and i bought this car because it was a deal that couldnt pass up. so how do i know if i am venting to atmosphere or not?? Either way, how do i tune the bov to get positive results?

Its cool. We were all new at one point.

If there is a pipe that runs from the BOV back into the intake tract then you are NOT venting. If there is nothing connecting the BOV to the intake then you ARE venting. DOnt vent.

Michael

 

[4G63 GST]

He has a Greddy so what does cruchins a 1G BOV have to do with anything???

Alot actually .. .. the process of crushing as most know its done to tighten the factory bov spring inside the bov. The tighter spring tention caused by crushing is what keeps the rpms from randomly jumping. Same with a vented Greddy.. you will have to adjust the spring tention accordingly to keep eratic idle at bay.. my friend had the type s and had a similar problem until it was adjusted. The true question is if he is venting or not .. like mentioned before .. if the system isnt vented then its more than likely not a bov related matter.

Luke

 

[TurBoGs-T]

if the system isnt vented then its more than likely not a bov related matter.

I disagree.... He said "Its currently only has about one thread exposed"
which means that it's extremely tight. Having it too tight can be the problem because if he's not running enough boost (and i highly doubt he is) to make it open, then all the air is going to rush back into the turbo (which is probably where that flutter is coming from).If you have the bov set to hold 30psi but you are only running 13psi that will be a problem. So what you need to do is back that screw out most of the way and start tuning from there if you can do a run and your boost is solid then it's fine.

 

[jonseclipsegs]

ok, thanks for input so far. i went and checked out car...i am NOT venting. with that out of the way, what is causing my low rough idling and by fluttering blow off? Fix?

--also, my air/fuel guage is reading lean then jumping to rich and my vac is a little less than 10 when its idling(rough).

 

[y2slic]

ok, thanks for input so far. i went and checked out car...i am NOT venting. with that out of the way, what is causing my low rough idling and by fluttering blow off? Fix?

--also, my air/fuel guage is reading lean then jumping to rich and my vac is a little less than 10 when its idling(rough).

^^^^^^^^

sup, beneath the car in the exhaust piping check the o2 sensor make sure it's in place with no movement or leakage, the o2 sensor loose will cause your car to idle in rpms like it's gonna stall and come back up.

peace

 

[dave99gst]

All I know is that the air fuel gauge jumps like crazy from rich to lean when I idle.

thats the sign of a healthy o2 sensor. ( normal )

 

[y2slic]

thats the sign of a healthy o2 sensor. ( normal )

ya i know the sensor is healthy i put it in myself, but there's a bolt that the sensor screws onto that was missing so i had to apply high temp. adhesive to the sensor, which has a long life and strong hold, but the car is dropped so low that any bump on the road can hit that sensor and knock it loose, so u gotta check if it's loose or still tight.