Mr. LS VTEC

Why does my car die after I unplug the IACV? I have a few other posts about my problems but I would like to address this one sepparately. Any info would be awsome.

fmrprojects

mine does the same thing. why would you unplug it for

miahmouse

it's supposed to die or nearly die when the iacv is unplugged... it's normal...
edit:
you would unplug it to test the IACV... if the idle doesn't drop, your iacv is fubar...

EJ1 wilcox

Your base idle is too low.

If it's too low, the IACV will compensate and keep it running while plugged in. So when you unplug it, it will die.

The idle needs to be adjusted so that with the IACV unplugged and the service port jumped, the car idles at 750RPMs (or something like that). After you make the adjustment with the IACV unplugged, turn the car off, plug the IACV back in, unjump the service port, and pull the ECU fuse to reset the ECU. Then put the fuse back in and you are good to go.

Make sure you adjust your idle screw with the IACV unplugged. If you attempt to adjust your idle while the IACV is plugged in, the IACV will automatically compensate for any changes to make and you will not be able to adjust the idle properly.

I hope that made sense.

miahmouse

or if your car idles fine with the iacv plugged in, leave it the hell alone...

Mr. LS VTEC

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EJ1 wilcox &raquo;</TD></TR><TR><TD CLASS="quote">Your base idle is too low.

If it's too low, the IACV will compensate and keep it running while plugged in. So when you unplug it, it will die.

The idle needs to be adjusted so that with the IACV unplugged and the service port jumped, the car idles at 750RPMs (or something like that). After you make the adjustment with the IACV unplugged, turn the car off, plug the IACV back in, unjump the service port, and pull the ECU fuse to reset the ECU. Then put the fuse back in and you are good to go.

Make sure you adjust your idle screw with the IACV unplugged. If you attempt to adjust your idle while the IACV is plugged in, the IACV will automatically compensate for any changes to make and you will not be able to adjust the idle properly.

I hope that made sense. </TD></TR></TABLE>

Ok well first off, I'm running a Power FC, is this going to screw up this whole procedure? It isn't tuned yet. But if it is the same procedure and I have already been messing with the idle screw then would I have to reset the ecu and start over again? The reason that I'm posting this in the first place is because my car surges about 500 RPMs. NOT just at idle though, if I hold the throttle down then it will surge at any RPM. Is this a tuning problem? or a rouge vacuum leak. I've searched all over and cannot find a vacuume leak anywhere. Thanks for the quick replies.

miahmouse

if it surges at all rpm I'd say it's a vacuum leak... bust out some starter fluid and start checking... or rig up a fitting so you can pressurize the IM. pretty much a pressure regulator(ala leakdown tester) and an air fitting into the correct size pvc pipe w/cap into where the intake connects... put a couple pounds of pressure in there w/throttle body open and listen for leaks... (pvc part should look like a cup with an air connector on the bottom)

Mr. LS VTEC

OK, well I'm not going to be like a lot of other people and just not post the fix to my problem after I found it. The reason that the Idle was surging was because after I changed out my battery, I didn't compensate for the huge injectors with my Power FC, I'm running 880 injectors and the car hasn't been tuned yet. So what happend was the injectors were set at 100% and needed to be somewhere around 27%, that is until I get it tuned. Now the IACV was cutting off for an entirely different reason. I didn't adjust my new type-r throttle cable that I got for my OBX IM, and the cable had to much slack in it, so the idle was so low that the IACV had nowhere else to go but off. So there you have it. Now I'm having a different issue that I'm goin gto start a new post for.

Thanks to all of those out there that helped me out.

miahmouse

thanks for the update, but I gotta request in the future that you state anything that isn't stock or that it hasn't worked correctly yet.... will help immensly in tracking down the actual problem...

And you should never adjust the idle with the throttle cable... it will eventually stretch out and you'll be back with the same problem... Make sure the stop screw is in the right place (throttle doesn't stick) then adjust the idle screw on the tb to set the idle.