leescotty2001

I have a 2001 Maxima SE i just bought. When the car is cold and I start it, it wont idle.. It will just cut off. I have to kinda give it gas, then hold rpms up for like 2-3 seconds or MORE then it will idle fine... When warm it will start up no problem. Feels like maybe clogged fuel filter but I am unsure... Was hoping someone would know before I start buying parts.

P. Samson

How many miles on the car? If the car performs OK when the fuel demands are higher, like on the highway, it isn't a clogged fuel filter. The fuel filter is in the fuel tank (on the suction side of the pump) and normally are good for a lot of miles. On a cold start once you get it to idle does it idle at about 1300 RPM and then slowly decreases as it warms up, and when fully warmed up does it idle around 700 RPM? Manual or Auto?

leescotty2001

122k miles... When I start it and then idle it with my foot on gas, then let go after a couple of secs... Idle then drops fast down to about 700 steady.

leescotty2001

o yea its a auto... idle drops to 500 when i let off gas then rises to 700 and holds cold or hot

P. Samson

The idle speed drooping to 500 RPM isn't normal even if it quickly recovers to the normal 700 RPM. Can you hear the IACV (Idle Air Control Valve) make a kind of buzzing noise for about a half a second or so when you turn the ignition switch from OFF to ON only (open the hood and have someone else turn the key)? The IACV is located on the underside of the TB housing. When you move the gear selector from N to D, what does the RPM do?

flatcat19

I'm with P. Samson. Suspect the IACV. And figure it out quickly, before it burns the ECM. I've seen it happen on 5 01 Maxima's, mine being one of them. Starts out just like you explained...then POOF! Once that factory smoke comes out of the computer, you can never get it back in there.

leescotty2001

I do hear a buzzzz for about a sec when key is switched from off to on. Not sure where its coming from. I had my head in engine bay area while my daughter turned the key. Also when I put the car into drive from neutral it goes to 500 rpms.

leescotty2001

I am in process of replacing IACV... I have to order it seems wrecking yards are fresh out of them.... Hopefully i got a good deal on this car... I paid $3900 heres a pic

P. Samson

I asked about checking the IACV for making the "buzzing" sound not because it shouldn't make it. The IACV is supposed to make a noise just as you indicated.......I was going to suggest checking for vacuum at the PCV valve and doing a manual cleaning of the throttle plate and throttle bore before doing anything else, but this may work out. It may well be the IACV. If you just change the stepper motor only it'll be easier than changing the whole assembly but make sure that you check inside the housing with a good light for any sign of crap/crud and coolant. In theory, you have to accomplish an Idle Air Volume Learning but see how it runs and idles first. The car looks in nice shape with a really clean looking interior.

leescotty2001

Do you know where you can find just the stepper motor?

P. Samson

You can't buy just the stepper motor. Just get the whole IACV assembly, remove the stepper motor from the IACV housing (two screws) and transfer it over to your TB. If you get a wrecker unit, before installing it on your TB pretest the stepper motor to ensue that it at least "operates" by hooking it up to the harness connector and doing the ign. Sw. ON-OFF deal again. Before installing the stepper it would be a good time to clean the throttle plate, TB bore, and inspect and clean the air passage and the IACV housing. Don't "flood" the throttle shaft area and contaminate the throttle position sensor with any cleaning fluids. Just make sure that you dry everything. If there is ANY sign of coolant in the IACV housing air passage you'll have to remove the IACV housing as well from the TB. The gasket (an "O" ring cross section type) can leak coolant into the air passage/housing and contaminate the stepper motor. Just be aware that the wreckers may not want to sell you only the IACV......they'll want to sell you the TB assembly which might come in handy later, I suppose, if the price is right. The other unit that should be on the TB is the throttle position sensor. DO NOT disturb it, by the way.