duba02

I have a 1jzgte (non vvti) swapped sc300 with a W-58. The engine idles high (around 1200 rpm) but the idle does not hunt it is very stable. I have read that it could be the idle air control valve. Last night I unplugged the electrical connection to the IACV and it had zero effect on the idle. Would you expect that if it has failed? Thanks!

duba02

I would really appreciate any thoughts on this question. I have searched everywhere and have not seen this item addressed. It idles consistently, just too high. Also, would love to hear about anyone involved in the 1jz Soarer community in the Cincinnati area, especially tuner shops. Thanks

RudysSC

It does sounds like your IACV could be bad based on no changes after un-plugging it (someone correct me if I'm wrong, please). You can also spray (be very careful with this) a little bit of starter fluid around your intake and intake manifold to check for a vacuum leak. If you hear the engine idle up then you know you're getting starter fluid (and thus air) in somewhere that you shouldn't. Start there and report back.

duba02

Thanks. I purchased a used IACV and will clean it with carb cleaner and swap it out also. It looks like new ones are around $800 even in Japan! That's a bummer. Does anyone know of a better option short of an entirely different ECU? Also, I think from reviewing old threads here and on other forums that the adjustment screws at the throttle body will NOT turn down the idle. I could see how that could cause a higher idle if the throttle plate is being held partially open because the screws are too far out, but it seems like the conventional wisdom is that this is not the case. Thanks again for trying to help. I'm new to the 1JZ and love it so far other than this apparent parts availability issue that is surprising to me.

RudysSC

There may be an idle screw on the TB but I'm not sure on the 1jz... As for parts, keep looking. The 1jz made its way into all sorts of cars over the years all over the world so there may be other places worth looking.

duba02

Thanks for the help!