need help

[brs86supra]

ok i have a problem with my bypass valve i believe. when i have it hooked up the car will idle like crap and will bog down and cut off but when i unhook it it idles just like it would if i were to unhook the afm. but when i give it gas it kinda dies. so i tried to blow through the bov but nothing happened, but wut makes it weird is last week i was able to blow through it (which i know is a sign it is bad) but yesterday i couldnt. so does this mean my bov is bad and could be my problem. i have no codes and timing is right.

 

[ATL88Supra]

im not sure if i understand this question,

are you saying that you think your bov is leaking ?

bad idle is most of the time cause of the iscv going bad or clogged

or the afm is dieing but sense it dies when you hit the gas i am going to have to say its the afm, or a MASSIVE Intercooler pipe leak...


have you checked codes ? CEL bulb ? are you able to read your AFR's ?

just cause you have no light wont mean you dont have codes...

now if you really have no codes then force one, pull the afm plug

then check if the CEL light comes on while it is unpluged then reset the ECU effectively wipeing anycode or ecu problem( kinda like a desktop rebooting sometimes fixes crap ) plug in the afm (check codes).

if nothing shows up i am betting its a leak or the bov

 

[brs86supra]

i am saying that i think its my bov b/c i think is defective. i have already checked for codes and havent gotten any. and the afm is brand new so no bad afm.

 

[jetjock]

Are you talking about the stock CBV? If so it being open or closed will have zero effect on idle. If unplugging yours (which closes it because it's normally open at idle anyway) is effecting how the engine runs the problem lies elsewhere. That said if you're talking about an unrecirculated BOV that's a different story.

 

[Kurb Appeal]

If he was able to blow through it before and not now wouldn't that be a bad bov spring? He shouldnt be able to blow and make it open, at least none of my friends can they thinks its a game..???? Any ways just something I noticed.

 

[brs86supra]

yeah im talking about the stock bypass valve. so the bypass valve is probably not my problem then correct? cause ive checked for codes and havent gotten any.

 

[jetjock]

Nope, not your problem, at least not your idle problem. In fact a bad (open all the time) stock valve won't effect much even at full boost because a healthy turbo can easily overcome the "leak". I've changed many a stock valve where the owner has driven around for months and not known it was bad.

Course, I'm assuming when you unhook the valve you're covering the end of the hose. If not idle will be effected by the vacuum leak.

 

[brs86supra]

yep sure am. well last time this was happening, which was like last week or so one of my fuel injectors were not firing. i came to this conclusion b/c my spark plug looked brand new and never touched and alll the other ones were pitch black. oh and forgot to say that i am in the process of a na-t swap. and i just replaced the woodroff key in hte crank. but the timing is set right. everything is all aligned up right.