Wonky Idle

[Skym]

If airleaks are bad enough they can affect starting, idle. At least that's what I have experienced.

[Stuntmonkey]

Cleaned the crap out of the IAC valve tonight with carb cleaner, took a lot of qtips lol. Didn't make that much of a difference really

[TheyKilledKenny]

The highlighted part is the IACV correct?

[Skym]

23781M is the AACV

22660M is the IACV

[TheyKilledKenny]

Ive cleaned the AACV but not the IACV, looks like I might have to remove the plenum to get to it.

[Stuntmonkey]

Ah so I did the AAC, not IACV.

[Skym]

IACV should be able to be removed, cleaned with top part of intake plenum in place. Just have to move all the hoses, etc above it out of the way. The IACV sits next to throttlebody on top of the runners on lower part of intake plenum.

[TheyKilledKenny]

Ill have to take a better look, thanks Skym.

[nelsonmxmarc]

What condition is the gasket in, from the AACV? Usually they tear when removing, this will increase idle rpm (lean condition)

[Stuntmonkey]

My gasket was ok, I should really put a new one on though, who sells them?

[nelsonmxmarc]

eBay is usually your best bet.
You can get a full oem Nissan engine repair kit for 150 shipped vs 300 elsewhere.

Also, if it's your iac at fault, rather than change units, you can delete it. I've removed mine, just need to adjust cold start values to make due with the small decrease in air. Tps can account for it. I'm more familiar with nistune in that department, so I'm not sure what 3rd party application you're tuning with.

[Skym]

Interesting thing I found out, oil makes a big difference to idle (engine can struggle to idle due to using too thick oil). Also engine (lifters, etc) can be alot quieter with correct oil.

[Stuntmonkey]

Well it's not my iacv! It's practically brand new. Opened it up and it couldn't have been cleaner.

I'm looking at my tps and coils now. What's the best way to identify a faulty tps?

[nelsonmxmarc]

Voltage.

The middle wire on the harness is white - Place the volt meter positive lead on this wire (make a small incision to do so because it has to remain connected), then ground the negative. Set to two digit reading, you should see a value. Closed should be .48-.50 . Fully open is..... 5.00 volts? I completely forget off the top of my head. At any rate, if you fully open the TB and it doesnt extend past 3 volts, then you can almost guarantee its donezo. Another way to tell is that when trying to adjust voltage (loosen top bolt, rotate left and right to achieve desired voltage) it will not reach .50 volts closed, if anything at full tilt, it will only see something like .38 v or so..

Hope this helps! But unfortunately i believe its still the IACV.. mine was clean too, but the circuitry can surpass any visible signs of failure.

[Stuntmonkey]

Ok thanks I"ll give that a try. Gotta try and find my bloody volt meter now haha!

If I decide to bypass tps, I can just connect the 2 vacuum hoses with connector pipe I guess. Can tire should have those?