A/C is out and have some idle issues.

[fastpace]

I just finished my week long project of taking out the a/c system, changing lower radiator hose, turbo gaskets, and thermastat. I let the car warm up and took it around the block, car feels very responsive and really like how everything still works the way I want them to.

However, I have noticed an idle issue. The car idles normally at around 900 rpm, but at times it fluctuates at 600 to 800 rpms for 6-7 times and then it idles fine at 900 rpm. I have checked all of my vacuum lines and they are fine. I also checked my compression and very consistent to each other and high like it used to be. At 900 rpm the boost gauge reads 500 mm Hg.

Just wondering if anyone has any suggestions of what I can possibly check to help fix the problem?

My setup:jwt ecu 50lb programcobra mafs550cc injectorswalbro fuel pumpT-3 super 60

[fiznat]

does it only do this with your AC power on or off? ...or doesnt it matter?

Also try cleaning your MAFS, sometimes a dirty or worn MAF can cause an erratic idle

[fastpace]

it does this whenever. I will try to clean the mafs tomorrow, thanks for the heads up.

[fiznat]

other things that it could be:

-coolant temp sensor (there is an idle adjustment table for this, so if you're gettin weird readings off of it you could get a funky idle)

-bad IAC (Idle air control: could be dirty or broken... this regulates your idle so obviously its one of the things that could be at fault if your idle gets weird)

-Fuel filter (could be getting junky fuel at low pressures)

-Bad air filter (worth checking)

-Small woodland creature living under dash and playing with gas pedal just to watch you squirm. (they're little devils I tell you!)

[Ubernoober]

Don't forget to take a look at the O2 sensor. I had a bad connection to mine and it caused the symptoms you describe.

[fastpace]

I just also noticed that I am leaking fluid from the bottom of the water pump, so I am thinking my waterpump is messed up and need to be change. I am going to replace it tomorrow.