Rooster286

I guess this forum is both a blessing and a curse

Starting today, for god knows what reason, my car when idleing is hanging around 300-400 rpm. Almost at stall stage. Power steering is locking up because the RPM's are so low. I have no problems when I use the accelerator to manually jump it to 800-1000, but I have NO idea why it would start this all of the sudden. There are no weather changes or natural variables that could account for this. Perhaps one of the Guru's has some advice, aside from manually turning up my idle, since I'd like to find out just exactly why it has started. Any help is appreciated.
(i've done nothing to it whatsoever btw)
Thanks!

95 Maxima GXE
S&C Package
Auto
93,000 miles

Daniel B. Martin

Here is some text copied from the factory service manual.

"Idle Air Control Valve (IACV) -- Auxiliary Air Control (AAC) Valve

This system automatically controls engine idle speed to a specified level.
Idle speed is controlled through fine adjustment of the amount of air which
bypasses the throttle valve via the IACV-AAC valve. The IACV-AAC valve
changes the opening of the air bypass passage to control the amount of
auxiliary air. ... "

You may make a quick test of your IACV-AAC in the following way. With the
motor at normal operating temperature, and at idle, switch the A/C from
"off" to "maximum". Keep your eye on the tachometer as you do this. The
idle speed should dip momentarily and then recover. If it does this, the
IACV-AAC is working. If the idle drops and does not recover, the engine
may stumble, falter, and stall. The IACV-AAC may require cleaning,
adjustment, or replacement.

The correct idle speed is...
- 700 +/- 50 (automatic transmission, in Neutral)
- 625 +/- 50 (5-speed)

Here's the factory service manual component inspection procedure for the IACV-AAC.

1) Make this test with the ignition key OFF. Disconnect the IACV-AAC valve harness connector.

2) Looking into the valve connector with the latch at the top, you will see two rows with three terminal positions in each. They are numbered 1-3 (top row, right to left) and 4-6 (bottom row, right to left). Check resistance between the following terminals.
2 and 1.
2 and 3.
5 and 4.
5 and 6.
At a temperature of 68 F, the reading for all measurements should be approximately 30 ohms.

3) Reconnect the IACV-AAC valve harness connector.

4) Remove the idle air adjusting unit assembly (IACV-AAC valve is built-in) from engine. The IACV-AAC valve harness connector should remain connected.

5) Turn ignition switch ON and OFF, and verify that the IACV-AAC valve shaft smoothly moves forward and backward. If NG, replace the IACV-AAC valve.


There are other engine parts which play a role in maintaining the right idle
speed, but the IACV-AAC is the first thing to look at. Good luck!

Rooster286

Wow, thanks a million Dan. Greatly Appreciated!

It'll be the first thing I check this weekend.

Rooster286

I was browsing through the search forum for idle speeds...and notives the http://forums.maxima.org/showthread....highlight=IDLE

ECU Selector Thread.

I just thought it over, and realized that I never had any idle problems untill I checked out an ECU code. I rememebr the label saying IDLE on it too....most likely that is my problem, but I plan on cleaning out my throttle body anyway, and want to update and thank you for the info.


-Martin.