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Discussion Starter · #1 ·
Car doesn't always idle right, some days its fine most others it does not. Its been doing this for the past 2-5 days, also no cel. A battery light does come on, read below for when.



The car will sit between like 400-800 and bounce around. If it bounces lower than 400 it will jump up to above 1k by a little. After about 5 seconds of bouncing around the car will die.



I took a closer look at the car for any lights to come on while it was bouncing and the battery light Came on during the =<400 rpm mark.



Things that have happened to the car recently:



solenoid and canister were replace back by the gas tank(thx iminhell, you were spot on w/ that one). Drivability has improved.



Some corrosion was cleaned off of negative terminal via baking soda.



Car has needed a jump a couple of times after it didn't want to start immediately.



I would like to put my opinion but that's been proven to be a bad move before.
 

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C2H5OH
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Idle RPM is controlled by the IAC.
The IAC is controlled by the TPS.
Fuel and spark are controlled by the MAF and TPS.

There are a couple situations that could cause a lower than expected idle, too little air or too little spark.
In the too little air situation, the IAC is not opening enough. If it's working properly this is probably because of old and corrupt stored data. Something like you didn't do a computer reset after replacing a part (EVAP Solenoid).
In the too little spark situation, the MAF may be dirty. If it's registering less air flow than actual it will command a lower load and spark.

IIRC you have cleaned everything previously. So I'm going with the not doing a reset being the problem.

Also, I've found that using a light oil on the IAC works better than cleaning it with something like brake or carb cleaner. PB Blaster, WD-40, Liquid Wrench or the like I think works better / seems to lube it a bit and it works better.
 

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Discussion Starter · #3 ·
So you're saying clean the maf w/ brake cleaner or isopropyl alcohol and things of the sort?



I'm assuming reset includes unplugging the battery? Because I did that when I cleaned the corrosion.



pull the fuel rail off and clean the iacv w/ wd40? Just squirt a bunch in there?
 

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C2H5OH
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So you're saying clean the maf w/ brake cleaner or isopropyl alcohol and things of the sort?

Use MAF Cleaner:





I'm assuming reset includes unplugging the battery? Because I did that when I cleaned the corrosion.
Yes.



pull the fuel rail off and clean the iacv w/ wd40? Just squirt a bunch in there?
Fuel rail doesn't have to come off.
Getting to the IAC is a PITA. But squirting some WD down the hole in the TB leading to it does seem to work if left sit overnight. It's not optimal, but works. Best thing to do it to remove it to clean it, but you either have to have pipe cleaner arms or remove the manifold to get it off.


Just shoot some WD down the hole on the right side:

 

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Discussion Starter · #5 ·
I have the bbk one... So I don't remember which hole that was.
 

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Discussion Starter · #6 ·
I'm assuming the only hole in this is where the wd40 goes?

Not my TB but one from a pm.
 

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