Picture TUT ULTIMATE ISC FIX! 1 catch!

[CyFi]

DISCLAMER: IM NOT RESPONSIBLE for anything you do to your car. This is a guide that you can choose to follow if you want, but do it at your own risk. Im not responsible for injuries, damage, or anything that happens in the process of following this tutorial, Thanks.


I will start with a little background information and ways to check if your isc valve is bad.

Well, when you start your car, your idle shoots up, goes down sometimes, doesnt other times, contsantly inconsistant and high. First thing you should do is remove your intake tubeing, run the engine until its 100% warm, and put your finger over the little hole in the throttle body, just inside there, impossible to miss. If it sucks your finger it and cures your high idle, youve got either an ISC problem or a water temperature sensor problem, or a number of other things. But if you're like me, and dont want to go through all of that bull ****, just follor my tut, its really not as hard as it may seem, and i finished the whole thing in less than half a day.

The ISCV (Idle Speed Control Valve) is a magnetically controlled valve that opens and closes, either to let more, or less air into the engine, therefore revving it more or less. For some reason, in our 5sfe's, This valve causes non ending pain. It sometimes seems nearly impossible to fix, and nothing works. When this valve goes bad, or the cotroll mechanism goes bad, the valve stops opening and closeing like it should, and in most cases, stays open, cause the high idle. Sometimes there are sensors within the car that go bad, which tells the cars computer to keep the valve open, even when it shouldnt be. Though the skys the limit of the things it could be, some people persist to fix it, some are successful, some are not, im just here to help you gain control over that mother ****ing *****!!!!!..... Now, heres how my theory(proven) works.

By using the A/C VSV to our advantage, we can phisically control the allowing of air into the sysem with a switch. Now, if you have an air conditioning system that is functioning, im sorry, but this one isnt for you. If A/C was not an option selected in your mr2 NA, you can still do this, but you will need to buy some parts that are already included with the AC compatible systems.

So again, The VSV is a system that is for the air conditioning. When the A/C Compressor kicks in, it puts a signicicant amount of strain on the engine, and if the engine is idleing too low, and the AC is turned on, the car may idle WAY low or even stall out. So to compensate for this, there is a valve that lets a set amount of air into the motor, increasing idle RPM's, keeping the motor running under the stress of the compressor. Now, if you have a damaged or removed AC system, this part is no longer used, and no longer works without the other components working properly, even when the AC button is pressed. Now there is a way to still use the same circuit and bypass something so you can use the AC button instead of doing all this wireing, but then again, i dont like half assing things. So now with a flick of a switch, you can allow more air into the system during cold starts when you need it, and switch the air off during normal driving, after the engine is warm, when you want that low idle for gas savings.


Ok guys, ive come up with the ultimate messed up ISC valve fix. Theres one catch, and im sorry, but you MUST have an air conditioned MR2 *WITHOUT THE AC WORKING* This means either the **** dont work or you removed any part of the AC system. Ok, i will start by giving some info on what we will be doing. Basically what i have done is come up with a way to totally block off the ISC valve and use that AC idle up valve to our advantage. Unfortunately, for the first few steps, i do not have pictures, as i didn't intend to make a tutorial out of this. I am going to do my best to make this as newb friendly as possible. I will start.

Im sorry if i have repeated myself many times, i did this at didffernt times, so its kind of mixed up!^

PRODUCTS NEEDED!:

1. A reel of stereo wire, can be found at radioshack, get a nice thick diameter. I got this (18- Gauge Spreaker Wire) (25 FT) WAY MORE THAN ENOUGH. You want to make sure you get wire that has 2 wires jioned, so you dont have to run 2 separate wires.

2. Swtich, Found at radioshack. I chose http://www.radioshack.com/product/in...tId=2062525&cp

3. "nipple" as i call it, its actually a brass fitting that i bought at Home Depot, Be sure to also pick up a dual sided one for the coolant lines.

4. RTV black works great

5. Zip ties, found them at the hardware store for a couple bucks

6. Small hose clamp for air hose.

7. Solder.

Tools needed:

1. Drill with drill bits.

2. Dremel is reccomended, for little grinding of plastic if needed, not necessary.

3. Soldering iron

4. Wire Stripper

5. Random assortment of sockets and screwdrivers.

6. A good pair of hands.


ISC BLOCK PLATE! (sorry no pics here)
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1. Ok, start by removing the throttle body. You will need to somehow clamp off the coolant lines so you dont leak coolant everywhere. Make sure the clips are moved off the end so the tubes can slide off.

2. Slide coolant tubes off, and center air tube off.

3. While you are here, you might want to grab some carb cleaner or brake cleen and detail this thing, if it was anything like mine, it will be caked with oil and grime.

4. Turn throttle body upside down. Locate the ISCV(Idle Speed Control Valve) which is held on by 4 Phillips screws. Again if yours is anything like mine, these wont come out.

5. If your screws come out fine, move to step 6. If they dont, keep listening. You will need to drill the screw heads out, sounded kind of scary to me at first too, but its not. Just get a drill bit slightly smaller than the diameter of the screw head and drill until the head of the screw falls off(or gets stuck on the bit like mine did, sorry dad ) Once youv got all four screws drilled, slide the ISCV strait up and off, and use vice grips to clamp onto the threads that remain, and unscrew it. Now, go down to the hardware store and buy some hex head screws of the same diameter, length, and pitch, with some washers, and bring them back home, use these when putting the iscv back. It is important you buy hex head or allen head screws, as they are easy to remove.

6. Now that you have the ISCV off, you will want a nice thin sheet of sheet metal. Cut this metal to about the size of the ISCV base, a little larger. Now drill holes for the 4 screws in the correct places.

7. Now you need to make a decision. Either you will cut out a hole in the metal for the coolant to run through, which i strongly encourage you dont do as it will more than likely leak, or you get a coupler, and tie those two coolant hoses you removed earlier, together. I strongly reccomend this, and has no ill side effects unless you live in extremely cold weather.

8. Seat the rubber gasket into the throrrle body side, if it is not already there. Apply some RTV to the ISCV base that you removed, which contains the coolant nipples and sandwich the sheet metal between the throttle body and the ISCV base, and tighten it all back up. Replace the throttle body back on the car.

You have now successfully 100% blocked off any air for the ISCV, and have a very good seal. I prefer doing this over something very half assed like shoving a clod of something down the ISCV hole.

[CyFi]

IT IS TEH TIME FOR TEH CONTROLSZZZZ LOLZ!!1!......sorry.
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1. First thing you gotta do is remove the intake tubes. Loosen the screws that hold the band.
******

2. Next you will want to remove that large heatshield by removing the nuts. I found it works best to remove the nuts circled, and kind of just move the heatshield out a little, you only need a little room.
******

3. Now move to the interior, You will want to start with the surrounding plastic around the stereo unit. Pull the ashtray strait out revealing the 2 screws holding the surround down. Now this should pretty easily pull out, one clip at a time. There are a couple things attatched, like the cigarette lighter, Cigarette lighter light, and emergency flasher button. You will want to unclip these sets of wires and set the whole unit off to the side and out of the way.

4. Now you want to move the the center console. This is the long armrest thing that goes all the way to the back. Start by removing the shiftknob but turning it counterclockwise, then remove the leather boot. After this, there will be a plastic base that pops out with four clips, pull hard but gently focusing on the 4 corners.

5. Next, at around the spot where the ashtray was is a supporting bar, running perpendicular to the length of the armrest. This has 2 screws in it, remove them.

6. Next you will want to look at the side of the armrest, you will notice two button like things on each side of the armrest, you will need to take a flathead screwdriver to pry those off, but remember to be gentle. After that, you will see the 4 screws, remove these screws.

7. Now slide the whoole unit strait up and out, it should come out pretty easily, just set that someplace safe for the time being.

8.Now at the back end, you will see a flap of what seems to be some sort of insulation, just hold that up, and you will see a sort of plate held by 2 nuts. Remove these.


8.After that, slide the metal plate back, revealing the rubber. Sort of pull on the rubber until it comes out of the hole, revealing light, this goes directly to the engine bay.(light meaning sunliught in the engine bay)

9. Now is where you want to get your wire. You want to shove it through one of the holes in the rubber, along the shift cable, push a long amount through, as you will need a bit, and can always trim it later. Be careful not to rip the rubber like i did, although im sure its not a huge deal.


10. Now go back to the engine bay, and pul the wire through behind the heatshield, you dont want that hot exhaust manifold melting the wire. Pull it through to the gas tank filler neck side of the engine, and figure your own route to get back right behind the throttle body, you will want to use some zippie ties generously to secure it, this is what mine looked like.


11. Now you need to break out that soldering iron, I reccomend a 30 watt iron. You will see a black connector plugged into a little black box that has hoses coming off of it, you will want to unplug this connector from the box, and snip the connector off, leaving a nice amount of wire to work with on the connector.


12.Strip the wires of the connector, and the wires you just routed around. Solder these together and use heatshrink on these, its important you use heatshrink so its hard for moisture to enter.


For added protection, i used a larger piece of heatshrink over the whole deal. Keep in mind, the polarity of the wires are not important, and the unit is not polarity-sensitive.


13. Go back in the cabin, and get that stereo surround again, we are going to tap into the cig lighters power, I chose this, it may not be the best choice, feel free to find your own 12 volt source. This may be the hardest part of the whole job. Its really hard to get the solder to stick to the metal of the cig ligher, i managed to do it for the center pole(positive) and then loosened the nut, and shoved the negative wire underneath, and then tighened it down. You may need to get imaginative with this, and find your own way, or find a different power source, im just glad im done with it....



14. Time to drill the shift surround. THis is where i chose to place my switch. A tip that i have, is dont drill too far close to the retangular hole, it almost interfered with the shift but when i was done. Center it nicely and make your cut.


15. Time to wire the switch. Around where we are going to mount the button, cut the red wire, and only the red wire and strip it. You have to now add length to both red wires by soldering more wire to it, i know, its a pain, but you gotta do it. THIS IS IMPORTANT! MAKE SURE YOU SLIP THE TIGHTNEING NUT AND SHIFT SURROUND ON THE WIRES BEFORE YOU SOLDER, IF YOU DONT, YOU WILL HAVE TO DO THIS ALL OVER! Now, Solder one free red wire to the center pole of youre switch, and the other to another pole on the switch (depending on which way you want the switch to be for enabled/disabled)





16. Now, you're getting close, Time for a beer(im under 21, i got a soda )

17. Ok, time for assembly of the interior, Put everything back the way you took it out. Now youve got a nice looking clean switch.



18. Go back out to the engine bay, and put those nuts back


AIR VALVE!
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Time to work on the air valve! This is where we will suck air for those cold starts, of course, we dont want unfiltered air! Do we?

1. Take your intake tube, and drill a hole large enough for your nipple to screw into tightly. You will want to drill this hole in the center of the first right angle bend, and on the bottom.

2. Screw your nipple on half way, now add some RTV around the threads like so.


3. Continue to screw down until you are all the way in, do not over tighten!

4. Wipe away some of the excess rtv and clean your wrench of the stuff, as it likely got on there.

5. Add more rtv all over the seal, to make sure air cant leak in, Let it dry.


6. Clean the tube thoughroghly to make sure no plastic shavings get in the motor

7. Install the intake tubeing back and slide the tube from the VSV over the "NIPPLE" and use a hose clamp to secure it.


YOURE ALL DONE! With the flip of a switch, you can enjoy easy starting, and with another flip, you can enjoy the gas saving low idle. I cannot garuntee that this valve will give you enough air for a cold cold cold start, because i am in california, but it did work suprisingly well for me, and i hope it all works out for you!.

EDIT!!!!!!!!!!! I HAVE CHANGED MY MIND! You can do this in a system that has a fully functional air conditioning system, all you have to do is buy the extra parts and tubes. IF THERE IS INTEREST FOR THIS, IM MORE THAN HAPPY TO TELL YOU ALL THAT YOU NEED FOR ANY SETUP!

If you have any questions, coments, or suggestions, feel free to PM me at any time. Happy modding.

I will post up a video of a cold start tomorrow once all my rtv is done drying and its all put together, and i will show you my low idle!

[Enthalpy]

Don't idle it below the factory specs. You won't save much gas at all, and the oil pressure will become insufficient to support the crankshaft and connecting rods. You will eventually spin a bearing.

Nice idea, though. The screw on the valve is an adjustment, so even if you live in a cold place, you could possibly make this work by opening the screw.

Very nice writeup! You should put your writeup talent to work on other poorly-documented procedures.

[Mister2.2]

Originally Posted by Enthalpy

Very nice writeup! You should put your writeup talent to work on other poorly-documented procedures.

Agree.

[CyFi]

Originally Posted by Enthalpy

Don't idle it below the factory specs. You won't save much gas at all, and the oil pressure will become insufficient to support the crankshaft and connecting rods.

You can use the idle adjustment screw to compensate for any idle thats too low. Just remove the rubber cap and turn clockwise to lower idle and counter clockwise to raise it.


Thanks for the compliments by the way

[CyFi]

you might not want to try this yet, i think the bending of the tube is putting too much resistance and not letting enough air, so its still not starting perfectly every time, you have to give it a little gas, but after like 2-3 seconds it stays at like 1100 rpms and doesnt die, so just hold off a while

[V6'er]

My observations:

1. Using the original Idle Up solenoid valve allows you to adjust the idle, AND, it's already filtered air. (I have no idea where you got the idea it wasn't.)

2. If your A/C is out, just unplug the compressor wire and short the pressure switch in the frunk. Now it should work to raise the idle because it will turn on the A/C relay when you press the dash button. No extra wiring required.

3. You do NOT need to drill out the ISC screws. You simply need to use a 15 dollar impact driver. (Hammer type.)

4. This is just dumb. Do it right and fix your car correctly like you should have done in the first place.

[CyFi]

wow thaks for accepting new ideas

[V6'er]

You're welcome.

You might want to accept some constructive criticism.

[CyFi]

sure, but you dont have to say its dumb, especially if it works

[V6'er]

Frankly, I think it's dumb to spend SO much time to make your car run less than well. Just fix it right. Sorry, I'm an old guy, old school. I like things done right. That's why if you look at MY V6 install, it looks like Toyota put it there.

But hey, that's just me talking.

[Enthalpy]

V6-er -
You must be one of those people who insists the world must see things the way you do. What if I told you that a V6 MR2 wasn't the "right" way of modifying an MR2? CyFi is having fun with this, and it's an exploration into possibilities. He knows it's not the published correct way to do things, he's not an idiot.

If he has fun and this leads to better understanding on his part about how cars work without hurting a single thing at all, then why not?

CyFi -
Shoot for a cold idle of more like 1500 RPM. This will allow you to cold start better.

If you wanted to get fancier, you could do a separate "cold start valve" that you would open to cold start the engine, but then close before the engine starts racing.

[V6'er]

I am a perfectionist, and as such, I like it done RIGHT. Half-assing an MR2 is done wrong.

As an electronics engineer for over 25 years, I'm qualified to tell you what's right.

That, and, I don't give a rat's arse what you think.

[CyFi]

ko well simply put, this is my way of not spending 700+ for a new throttle body

[V6'er]

Yeah, IF that were your problem, which it's probably not. If it's the ISC, it's totally adjustable and rebuildable. (It has nice tiny ball bearings, which people gum up by flushing the throttle body with solvent.)

[CyFi]

look i dont want to argue with you, but i think i know my own throttle body more than you do, and you dont know what i have tried or what i havent, so accpet this an an option if someone has trouble and doesnt have the money to fix it after trying many things

[Enthalpy]

Originally Posted by V6'er

I am a perfectionist, and as such, I like it done RIGHT. Half-assing an MR2 is done wrong.

As an electronics engineer for over 25 years, I'm qualified to tell you what's right.

Stop the presses! We have an arrogant engineer! Wow, that never happens!

Like I said, I didn't actually disagree with you about the "proper" fix for his issue. I simply disagree with how you approached this from the start. He's learning things about how cars work here. That's valuable. HE'S NOT HURTING ANYTHING IN THE LEAST!

Please understand I'm not disagreeing with your statements. I'm disagreeing with your approach to someone's experiment. I'm a professional Mechanical Engineer. I only criticize jobs when I'm asked.

That, and, I don't give a rat's arse what you think.

Likewise.

[V6'er]

Actually, between your posts and your PM's, I have a very good idea of what you've tried. And, I happen to know more about the way Toyota throttle bodies work than ten of you guys together.

So, what you did to yours to make it work better isn't awful, but since you DID ask me in a PM how to fix it, and you did not wait for a simple answer that would have been such a piece of cake to make work.

And for you engineers that only answer when you are asked, YOU were not mentioned in the PM that was asked to me.

What will be learned from all of this? Very little, except perhaps that there's a cleaner way to do things if you are patient with a goal in sight to do things WELL. This is a generational curse. Most of you have no idea you are stuck with it.

So I'll take my arrogance and enjoy it for my own purpose, but if you check my threads, you will find that I am usually very helpful and right on the mark with my comments and diagnoses. Sorry if you can't take my criticism, but then, you won't learn much in life if everybody just pats you on the back for your effort, even if your effort was misguided.

[Enthalpy]

I work at an R&D firm, Bell Labs as an engineer. An engineer won't last a year with this attitude. I don't think it's generational at all, I think it's merely related to perspective.

I obviously wasn't privy to the PMs. All I saw was someone thinking outside the box and being attacked for not doing it the right way. I jumped to his defense. I guess I shouldn't do that.

[CyFi]

Originally Posted by V6'er

Actually, between your posts and your PM's, I have a very good idea of what you've tried. And, I happen to know more about the way Toyota throttle bodies work than ten of you guys together.

So, what you did to yours to make it work better isn't awful, but since you DID ask me in a PM how to fix it, and you did not wait for a simple answer that would have been such a piece of cake to make work.

And for you engineers that only answer when you are asked, YOU were not mentioned in the PM that was asked to me.

What will be learned from all of this? Very little, except perhaps that there's a cleaner way to do things if you are patient with a goal in sight to do things WELL. This is a generational curse. Most of you have no idea you are stuck with it.

So I'll take my arrogance and enjoy it for my own purpose, but if you check my threads, you will find that I am usually very helpful and right on the mark with my comments and diagnoses. Sorry if you can't take my criticism, but then, you won't learn much in life if everybody just pats you on the back for your effort, even if your effort was misguided.

All i asked in your pm was how to make the AC button do the same thing as my switch, but in the end i thought it would be a lot better than i use the switch instead of an AC button because as said in my tutorial, i think thats even more half assed than doing it this way. Youre acting like that pm held vital information that says im retarded or something. I waited a day and a half for an answer and got nothing, so i moved on and did it my own way, i have other things to attend to. Just stop posting garbage in here and please leave the thread alone, its for other people to gain from, and if you dont like it, say the way you would prefer it done, though this is a nice idea as well...