help!! 240sx newbie rough idle, ac makes it worse

[splintercell]

heres the problem car idles inbetween 600&700 rpm,ac will damn near kill it.even when i am driving today i had to turn the ac off ,because it felt like it was going to stall.just got new magnecor wires and ngk plugs.rotor & cap.for the tune up,which it needed.did not help it much.could it be the aiv you guys have posted in the past,because i got rid of the intake box and i have the adapter with a k&N cone filter.also how do i adjust the idle.

sorry for all of the ?

ps.does a nissan 300 fuel filter help out much

[All_Motor_KA]

replace the fuel filter wit hthe 300zx, and buy a new gasket for the AIV. Take of your AIV and clean it up a lil if its dirty and put the new gasket on and see if that helps. Does your car drive fine other then the idle? Does it choke or hesitate?

[splintercell]

what year 300zx fuel filter should i use,or does it matter.the car runs fine besides just idle.when the ac is on it does bog down when im shifting.

[Atomic-S14]

where can i get a good price on the 300zx fuel filter?i think i need to replace it too since my car idles rough.

[zer0c123]

You can get it at your local parts store or dealer. You want an early 90's filte. i don't remember, but i think the 90-96 300zx all use the same one. Just flip through the car book at the parts store to see which one it is.

[JimmyMethod]

what year 300zx fuel filter should i use,or does it matter.the car runs fine besides just idle.when the ac is on it does bog down when im shifting.

You can adjust your idle speed... Personally, I like to crank mine up to around 5000RPM or so, so I never have to use the gas pedal...I just clutch and break...

[SlowBack]

You can adjust your idle speed... Personally, I like to crank mine up to around 5000RPM or so, so I never have to use the gas pedal...I just clutch and break...

I hope to God that you're kidding!

As far as the problem, I'd guess that your FICD is to blame for the drop when the a/c is engaged. The FICD (Fast Idle Control Device) raises the idle when there is an increase in load on the engine at idle (ie: a/c, alternator).

If this device isn't operating correctly, the extra load will cause a drop in RPMs.

Idling is one of the hardest things an engine has to do. It has to have just the right amount of fuel, air, and spark to keep it running. If you have idle problems w/o the a/c on, then you should take the advice of the others too (except for JimmyMethod). If the AIV is dirty, it could be allowing exhaust fumes into the intake. Engines can't run on their own waste (kinda like people ). If the car is breathing it's own exhaust fumes, it's gonna choke and give you a rough idle.

Hope that helps,Matt

[s86d]

nickel in the EGR pipe at the exh manifold will help prevent further isssues after you do all the other posted stuff. but you may fail emissions (dont know if VA has them.)-Dave

[Dattebayo]

Well, i dont know about these guys but If iwere experiencing idle issues while turning on my A/C, then I would check out the A/C related components, wouldnt you?

There are two things I woud definatley check, first being the AAC valve, located under the intake runners. Its hard to get at, but it controls the "idle up" function of the motor needed to run the A/C, as well as other motor-run accessories.

Also, Your A/C compressor may have a problem with it mechanicaly. It could be on its way to seizing up, low on oil or have a clog in the lines somewhere. You would be able to tell if this were the issue by disconnecting the drive belt from the compressor for a quick (and I do mean quick) check.

[splintercell]

just found out that my alternator was shot,that is probably the main issue,still taking out aiv,got all new ground wires,96 nissan 300 tt fuel filter,im sure she will run like a champ when that is all done.thANKS FOR ALL THE FEED BACK