[sjshredder]

well i have been having this problem off on lately and im stumped to what it could be. i started the car today and it ideled sooo rough and there was a weird humin noise coming from the intake on the turbo side, i reved it up and it shaked still and as soon as it hit 0 vacum and make a lil bit of boost it would just hit like a cut off and it almost sounds like a 2 step but its not. ive reset the ecu and it still does it from time to time but lately its doing it all the time.

 

[hiken]

What kind of mods do you have? Kind of hard to throw ideas out without knowing...

 

[sjshredder]

bpu still just have a map ecu2

 

[muchoboosto]

yikes! how old are your plugs? are any of them fouled?

 

[sjshredder]

they are pretty new. but im hearing a slith buzzin noise now from the turbo side, so i put my hand over the intake and let go and for some reason the car went back to normal but i still hear the buzzin

 

[muchoboosto]

is everything torqued to specs?

 

[sjshredder]

should be i never touched anything it just randomly does this.

 

[muchoboosto]

OVER the intake, meaning cutting off the air supply to the turbo? like putting your hands around the filter?


if so maybe a bad TPS? or MAF issues?

 

[sjshredder]

wwell i dont hav maf cus of the map ecu2. but i did get an intake air temp circut malfuntion but i dont know what that is and i figure it has something to do with the maf with i dont have anymore. but thats the only code i got

 

[muchoboosto]

oh yeah sorry, i forgot about the MAPECU.

 

[roliks]

any way to get a sound or vid of this said noise etc??

 

[sjshredder]

http://youtube.com/watch?v=7lWqpaRAGPw

just got the video as you can see its not to good but the car has a rough idel and is making funny nosies out the intake. it goes to like a cut off mode and shoots lean and some times it will go lean and then rich its weird.

 

[crazysupratt]

It sounds like the reed valve. I never heard it before but it sounds like what people decribed. The cut off might be because the engine isn't fully warmed yet or could be a off tune.

 

[muchoboosto]

wow that is not at all like what i had immagined

 

[sjshredder]

lol yea i have no idea what it is

 

[roliks]

IAC possibly

Intake Air control valve.

 

[Hwilli]

IAC possibly

Intake Air control valve.

LOL

So you just copy my post from Ohio Supras

It's located near the top, you should be able to reach down and open it by hand. If the sound goes away, that could be your issue.

 

[sjshredder]

got to remeber im still using map ecu2

 

[Hwilli]

Hang on I will find you a link.

 

[Hwilli]

http://www.max-boost.co.uk/max-boost/supra/turbo.htm

http://www.max-boost.co.uk/max-boost/images/supra/sequential/ReedValve_IACV.jpg

Open that actuator by hand and see if the sound goes away. Also make sure the vacuum lines look good, and it seems to be working properly.

You can use one of those mighty max hand pumps to verify the actuator is working properly if need be.

If the sound goes away when you open it, something is wrong in that area. Probably the reed valve as someone metioned earlier.

HTH,

Howard