How to clean K20 Idle Air Control Valve ( IACV )

                  I am making this post because... When i first started up my brothers K swap I was first excited that it was running well,, but after a min of smooth idle it would begin to surge. Which as most Honda owners know its most likely a Throttle Position Sensor ( TPS ) issue or a IACV issue. So after checking my voltage and correctly setting the TPS the motor would still surge once it was warmed up, (bummer)I did some research online and came to the conclusion that the IACV needed to be cleaned. all the articles said just take it off the throttle body and spray some carb cleaner in it and bam it should be fixed. Seems easy enough, bought some carb cleaner took off the throttle body and took the IACV off , sprayed the carb cleaner some black stuff came out. Put the IACV back on the throttle body, put the throttle body back on the car, started it and same issue once it was warmed up, surge surge surge. i knew there was something i was missing so i took it back off and just figured it out for myself. Below are my results, step by step on how to completely clean your IACV so it works good as new. feast on the fruits of my labor.


So Step 1.

 Is obviously take the throttle body off the intake manifold. you do this by taking a off  your intake, take off the throttle cable, remove the two small water lines that go to the IACV, disconnect the tps, disconnect the map sensor, disconnect the IACV plug, and there are 4 12mm bolts that hold the throttle body to the intake manifold. you should be left with this

 As you can see the IACV is on the bottom of the throttle body.

Step 2.

Get a Phillips screw driver and remove the two Phillips screws hold the IACV to the throttle body, make sure you press firmly on the screw driver as to not strip the screws out. Stripping the screws out isn't a life ender, but it would just be easier if you didn't strip them out.

Step 3. 

Pull the IACV off, it should come off with ease. Mind the rubber gasket and the two screws. i put the int he throttle body and set it aside so I don't lose any of them.

Step 4. 

You will now need to  disassemble the IACV, this is the most tricky part. You notice that the IACV sensor has two "star" screws holding it together, they aren't any Allen wrench sizes, and they aren't torx bit sizes. Im sure somewhere someone know hat tool to you to take the screws out, but i just use a grinder with a cut off wheel and just make a small slit in the head of the bolt to make it a "flat head" screw now.

Step 5.

Take a fairly large flat head screw driver and apply direct pressure and turn counter clock wise to loosen the two screws. I realize that in the pics it is hard to see the slits i created in the screw heads.

Step 6.

Now the IACV should come apart and you will notice that there might be rust, or other gunk in both pieces, this is where you will spray the carb cleaner into both parts to clean it all out.

Step 7. 

In the last picture from step 6 you see my left index finger is pointing to a small silver cylinder that has a small tab on it and a shaft the goes through a bearing. you must be able to freely spin this with your fingers this means that the IACV is going to be fully functioning. If yours is like mine and after spraying carb cleaner into it, it still doesn't spin. then you are going to have to use some WD-40 or other lubricant to free the shaft and allow it to spin freely. this is very important, The way the IACV works is is by sensing how hot the engine is and it does this by reading the coolant temp as it goes through the IACV. once warm enough it will allow the shaft to spin around blocking a small hole that allows the car to have a steady low idle, much like a choke. if this shaft cant freely spin then it can't properly block the small hole allowing air in, thus acting like a vacuum leak causing a surging idle.

Step 8.

 Now that your IACV is freely spinning with ease. ( note this might take some time, a lot of finger spinning, and WD-40 to continue to flush it out) if you don't take the time to make sure it is freely spinning then when you put it all back together its probably still going to surge. now re assemble to IACV using the two screws you made slits in.

Step 9. 

Re attach the IACV to the throttle body using the two Phillips screws and rubber gasket that you stashed in the throttle body for safe keeping. if you forget the rubber gasket then the coolant is going to leak into your throttle body.

Step 10. YOU'RE DONE!!!!!!! now just re install the throttle body and attach all sensors, hoses, throttle cable, and air intake. ( mine is missing a few sensor and im not going to be re installing it onto my motor, as the motor is currently not in the car and i need new gaskets) but this should help you get your car to stop surging. 

1JZ conversion

                                The guys at Mighty Car Mods have made a very cool video on how to do a 1JZ conversion. If you dont know who the Mighty Car Mods are, check out their Youtube channel they have numerous helpful tips for fixing up cars for. Its  pretty long video but worth the watch if you want to know about 1JZ swap basics.

BASIC DRIFT CAR SETUP 101

                  As most of you know i have recently finished up the build of my RB swapped drift missile car. this is my first drift car build of my own, i have helped many Friends build their drift cars and i have been around drifting for a while now. but this is the first time i am going to be drifting my own car. So two weeks ago i went out for my first drift sesh ever. i took the car our to U-DRIFT with some friends and had a blast. i think i did pretty well for my first time i only had 4 tires so my day was over pretty quick. but i learned a lot in that time, and i also learned that i have a lot to learn. here are two videos of me.




yes i did forget to torque the wheels after i changed them but i did remember before i went out.

I am well aware that my car is no where near set up properly for drifting. but with only limited funds im trying to figure out what the best choices in mods are that i need to make first.

here is my sub par setup

Tein coilovers that are 5 years old, blown out in every corner, cut springs to make the go lower from previous owner. but they were free and im glad that i was able to get them.
stock links
stock steering
stock knuckles
no front sway bar (because the rb oil pan hits)
stock rear sway bar
welded diff
stock seat
stock seat belt
stock steering wheel
no strut bars

so needless to say i have been searching through the mess of miss leading, incorrect, biased, stupid information found all over the interweb and various forums. today however i was able to come across some great articles on MOTOIQ.COM, written by Mike Kojima who we all know is the brains behind Dais drift car. these articles have helped me to see what is the most important things i can buy and what things i can do without or not do without. I wanted to post this because i know there are many other people out there trying to answer the same questions i have. i also know that these articles are a few months old, but i also know that not everyone is an Internet whore.

CLICK HERE FOR PART ONE OF BASIC DRIFT CAR SETUP

CLICK HERE FOR PART TWO OF BASIC DRIFT CAR SETUP



Hope this helps out some people.

HOW TO

This is a how to weld a diff for a nissan 240sx. ( this is just a guideline for people to use if they want to know how to do it. functiontheory.com is not responsible for you not doing this right)

ANYWAY. lets begin, we had an extra non abs diff laying around and since most of you know im starting to build a drift car. i decided to get cracking on welding up the diff. i know there is MANY mixed opinions about welding a diff... we here at FUNCTIONTHEORY.COM  have  personal experience on a few of our cars that we build. we have had no problems at all, for years on our drift cars with diff blowing up, or failing. so that is why u decided to weld it. besides i know most of you do it even if you talk crap on forums about it.

so the way we think we have made it so successful for us is we take A LOT of care doing it. i would say its easily a two hour job. and its super messy. the key is making sure you shield the ring gear with a towel so that any slag flying around wont get stuck on it. also you must THOROUGHLY wash all excess slag COMPLETELY out of the diff. this is the messy part. we used lots of wd40, and motor oil.

here are the steps

tools.
1/2 breaker bar with small 1/2 inch extension
14mm socket
ratchet
flat head screw driver
pen magnet
rags
oil

1. drain the oil out of the diff using the drain plug at the bottom of the diff cover.
2. reinstall the drain plug and them remove the 14mm bolts to take the diff cover off
3. take a rag and get most of the oil off as much of the spider gears as possible.
4. use carb cleaner or something similar to take the rest of the oil off the spider gears so you have a clean area to make a good weld on
5. COVER THE RING GEAR WITH A TOWEL BEFORE WELDING ANYTHING. the towel is going to have to come out ch time you have to move the gears to weld the other side.
6. make sure the spider gears are clean and dry. then tack all four corners of them on both sides
7. no go back to the first side you did and start welding the crap out of each cornermake sure the heat is up on the welder to get good penetration. do this to both sides ( DO NOT weld the ring or pinion gear)
8. allow to cool. we just let it air cool. we didnt want to make the metal contract to fast and possibly mess up somthing in the diff.
9. now here is the patient part. it is going to be a little hard to turn because slag might have gotten in the pinion and ring gear. so go very slow and DON'T force it. this is where you are going to use the flat head screw driver and break off all the slag pieces so they don't come off and BLOW UP your diff while your driving.
10. after you have gave it plenty of oil baths turning the gears while it is full of oil to make sure to get all the lose pieces of slag out you can use the pen magnet to get what ever else out you can.
11. making sure all the oil is back out and the diff turns with ease NO BINDING due to slag. if there is you will have to give it more oil baths and reach your finger in and try to feel for any pieces of slag. now you can re assemble. we just used some RTV gasket maker. and tightened up all the 14mm bolts on the cover. fill it with gear oil and your good to go.

to wrap it up. yes it does look a bit ugly but you really need to lay alot of weld on to be sure that nothing breaks off and wrecks the diff. again this is just the way that we do it that has shown great success for us. we are aware that there are other ways. but we choose to use whats best for us. below are a few pics.

CLICK HERE FOR THE FULL STEP BY STEP PHOTOS