chillin014

iTrader: (67)

After well over 2 years of putting off reinstalling the IACV I finally got around to it. I have the 3.5 motor and the IACV is sitting next to the passenger end of the manifold where the intake manifold butterfly plate would normally be, which has a nipple/connection for the output of the IACV. Then I've got the basic huge vacuum line run to the mid pipe which is mounted between the throttle body and the MAF. If this is confusing, I'll just snap a picture of it tomorrow.

Now originally it seemed like it was idling really high so I proceeded to tighten the screw and then it self-adjusted and went down to normal 700 rpm idle so I stopped messing with it. That is NOT the problem. The problem I'm having is this sort of rev-hang. I've never driven this car with the IACV AND 5 speed tranny. But it has introduced a bit of rev-hang between shifts which is actually quite nice. The problem is that anything below 2400 rpm and the IACV starts feeding air to the intake manifold and keeping the rpms up. This is dangerous because when I want to brake IN GEAR it is fighting me. It feels like a sticky throttle but my vafc reads 0% throttle and my a/f gauge does not max out like it would when I used to let off the gas. The IACV does not interfere at all above 2400~ I can decelerate in a gear and let off the gas and the car will slow down by itself until it drops to 2400 or lower.

I also want to report that my low first gear and second gear jolting has pretty much disappeared thanks to the IACV. Its a miracle!! I can see the iacv's purpose now. But I want to know if its possible to bring down the engagement rpm of the IACV. Does turning the screw adjust that? I'd never be in a gear below 1000 in most cases so it can engage at that point without a problem.

thanks.

njmaxseltd

iTrader: (19)

Have you gone through a true idle speed setup process?

Warm up engine, turn off, disconnect TPS, restart, adjust idle default stop on TB to 500-600 rpm's, turn off, reconnect TPS, restart and adjust IACV if necessary to abtain correct idle speed.

That process should setup both the TB and the IACV to work with each other.
Hope it helps you out.

IlyaK

iTrader: (47)

I don't exactly recall, but I believe I tried starting my car without the TPS and it stalled on me (I'm auto).

I have a similar issue...my car will randomly rev at stop lights, while in park, etc. It's not constant...happens for about 10 min and then stops for 6 hours...happens for 5 minutes then stops for 2 days.

It's very weird. I usually remedy it by cleaning the MAF and it's good for a couple weeks.

I'm hoping once I get my 00VI installed, the problem will go away.

chillin014

iTrader: (67)

I wasnt even aware there was such a thing. Where did you find this info? As Ilyak said, I'm not sure the car will start with the TPS disconnected. Do you mean disconnect the IACV and adjust the TB to 5-600 without the assistance of the tb and then reconnect it?

I have the PF TB and I'm afraid its a little quirky too. After I gutted my intake manifold I had to close the throttle body alot with the stop-screw to bring the idle down. The specs on the TPS are probably hella out of whack for the idle setting....I wonder if that could be part of the problem.

IlyaK

iTrader: (47)

It's in a sticky somewhere. But I'm pretty sure I tried it and my car wouldn't run for more than a second.

chillin014

iTrader: (67)

hmmm. I'll have to look for it in a bit. I was hoping this was more of just an adjustment issue but it seems like if I go and turn the thing all the way down its not going to do anything for me at idle.
this could be a TPS problem which will **** me off because I could NEVER get it in spec on the PF TB. its way too low on the closed position setting.

IlyaK

iTrader: (47)

Yeah and it ain't cheap. I paid almost $100 for a new one when I broke my plug on it.

chillin014

iTrader: (67)

alright I tightened the iacv screw down damn near fully tight and couldnt really tell a difference in driving. I'm wondering if the ECU being meant for the auto tranny has anything to do with it?

I'll play with the TPS in awhile, possibly change over to the one that is actually off of the pathfinder/came w/ the TB.

njmaxseltd

iTrader: (19)

The setup info was either in my Haynes manual or the FSM. Disconnect the TPS, not the IACV. When you disconnect it the ECU will run in limp mode, you will not set a CEL. The IACV will not be active.

Set your PathFinder TB so the idle speed is about 500.
*** Make sure the TPS is set correctly before you do this process!! ***
Follow my instructions above and hopefull your idle speed control will improve.

chillin014

iTrader: (67)

thanks. I'm gonna try it in a bit and see what it does

chillin014

iTrader: (67)

okay I went out there and messed around and probably accomplished nothing. The first thing I did was disconnect the TPS and the car shot up to about 2k (iacv still connected). Now I didnt even bother trying to adjust the throttle body stop screw because awhile back after I gutted the manifold the idle went up and I had to close to compensate for the high idle at that point...the throttle plate is BARELY opened as it is, I dont think there was enough room to drop the idle from 2k to 500.
I tried putting on the PF TPS but the ohms were way off when I was messing with it. The best I could get was like .9 at closed throttle and some low 3.XX number I believe for the WOT. The TPS on there now Reads 4.1 (as low as I can get it) at WOT. and .3 something at closed throttle. Of coarse that would raise if I could open the throttle more at idle but I can not.
I'm not sure if I've just got a crappy TPS or what but I cant get any info from other PF TB users as to if they have problems getting their TPS in spec and if it even matters. I dont know what the valve is trying to compensate for by allowing the air to enter at anything below 2400 RPM....at that point the TPS would be reading .3X as opposed to waht it should be (.5) so is that telling the IACV that not enough air is getting throughthe TB or what?
I want this damn thing to work!