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This install is super easy, but there's barely any info on it so I made this thread to help out those who may be confused.

It seriously takes 5 minutes. I do NOT reccommend taking this to the dealer to work out, because they will definitely rip you... the part is expensive enough as it is! Just order it from somewhere and do it yourself.

What you need is a 12mm wrench, a 10mm socket, pliers, and a rag. Don't use sockets on the Valve because it won't fit with a ratchet.

Here's how the car ran before I fixed it.

Click Here for the video

The car isn't warmed up in that video either, but it ran the same way when it was warm.

The code that is being thrown is P-1508.

Here is the part, I ordered it from AutoParts Warehouse for 188.44, and it was here ln like 2 days.




Here's the location of the part.


Use your 10mm to undo the battery. This is so the Check Engine light will reset and not go on after you're done.

After that, unplug the wires on the valve. Use your 12mm to undo the bolts, and use the pliers to take off those hoses attatched... place the rag underneath wherever you undo the hoses because it'll be a little messy, and remember which hose goes where on the IACV.


Here's the old one, it was pretty dirty.


Of course, all you have to do is just reattatch the hoses, bolt it back on and plug that bish in and you're all set, my car cranked right up and ran like a champ again.
 

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Awsome write up! I just did my 100,000 mile check and cleaned out my unit with good old Sea Foam arisal for about 15 min this stuff is awsome but, there is one thing that I didnt like about Honda's engineering on the IAC, a screen on the return side. Oh and the idle feels great But, How much them puppies run?
 

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if anyone didnt do this yet on 90,000 + do it recommended if you don't have money to buy one buy sea foam at autozone or parts shop and pour it or spray it and let it sit for 30 min and drain... honda made a screen on it and makes it easy to collect carbon on it there for makes the car idle funny..

awsome stuff LudeNLascivious

-Fixes idle and possibly shifting
 

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Rep added thank you for this, after reading this post I realized this may have been the reason my idle would bounce every now and again when i have the a/c on during stops it would drop to 200 or so rpm's then go up to 700 rpm's. Every maybe 30-45 seconds depending how long I am at the stop. I did not realize there was a co-relation to the two, also the 10 wompom I spent on a can of Seafoam and some elbow grease was better than spending at least a buck fifty I don't have I figured it was worth a shot. I spent about an hour and when you see the photos you'll know why. I will say one thing if I would have read just a few more posts on this I would have known to do this when the car is cool because the rubber hoses circulate coolant through the valve :exclamation: , and I didn't noticed that before so I got a little hot coolant today, all but burns and all mission completed, my idle no longer bounces anymore when the a/c is on, why is learning the hard way always funner?

Stats - 152k when I purchased my cyborg and in the two months I've brought it to 155k ( yes oil change this weekend ) but its never been done on this car as far as I know it had the original motor according to dmw, anyway this is definitely a fairly simple task even for the not so mechanically inclined


BEFORE:



Few bucks and some hands later:

 

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I do have one question as to this piece though, I read what the valve is but I didnt really understand it fully, why would it need coolant running though (I don't mean to keep it cool) meaning is it because of its location? of some other factor? How does this piece work is what I'm asking about in reference to what it does and not actually what the piece does.
 

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Just a quick question. I have a 1997 Sh model. Recently when I start the car it starts but then the RPM's drop so low that the car almost dies. It does this anytime I start it (doesnt matter if its first think in the morning or after 30 mins of driving). Also Ive noticed a couple of times when I stop at redlights it will idle around 1000-1100 RPM's.normal range is 600-800. Any one have any ideas. could the Idle control issues? thanks.
 

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Y don't you try cleaning it first and see if it changes anything.. Get sone carb cleaner and hose that thing down...make sure to remove the gasket BEFORE u start spraying.. Cost? Couple $ for the carb cleaner can.. Run some seafoam thru the pcv or brake booster line into the intake manifold..plenty cheap way to diagnose your idle problem..go try it.
 

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Anyone got a slightly more detailed explanation for getting it out to be able to clean it? I had a hard time getting around it to get everything disconnected =/
 

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Hey folks,

The former owner of my car unplugged the coolant hoses from the IACV and the smaller one at/near the throttle body (FICV?) What's the point?

Thanks!
 

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The reason why you unplug them is because you simply don't want the intake mani to get hot.

I did the IAC bypass which involves unplugging the hoses going to the IAC or IACV and damn the difference in temp is crazy my intake mani is much colder than before.

The other thing I want to bypass is the thermo fast idle valve but my idle is screwed if I do that unless I block off a certain hole with a new gasket.

Anyway try doing the IAC bypass. I also have a hondata intake mani gasket which has helped keep temps down too.
 

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Man, if you have the Hondata IM gasket, you definitely need to block off the FITV, you'll love it. You can make a block-off plate out of cardboard and an aluminum pie pan like I did, and seal it up with a bit of silicone. Or, you can go here and buy one if you're feeling spendy. I'm definitely planning on getting the IM gasket whenever I can afford the Euro-R, just didn't wanna go through all the work of removing my IM for just that one part. But just with the full coolant bypass, my plenum is nice and cold after a run! :D

But to the OP, the kiwi said it all. The throttle body has the FITV (fast-idle thermal valve) which raises the idle when the engine is cold through means of a ball of wax and a spring (seriously) which acts like a thermostat. When the wax is cold, the valve is open and your idle is high, but when it warms up, the valve closes and your IACV takes over. Blocking off the holes in the bottom of the throttle body allows you to ditch the FITV, and your IACV will handle your idle on its own. It'll still rise when the engine is cold, just not as much (which is good when you think about it, the high idle is mostly for cat light-off anyway). They also claim the coolant running through the TB keeps it warm to prevent icing, which is the same reason it runs through the plate bolted to the bottom of the IACV. I have yet to hear of anyone having this problem, even in cold climates like Canada, so have nothing to worry about living in Jacksonville.

BTW, you can just remove the brass plate from the bottom of the IACV if you want, so it doesn't look like anything is missing.
 

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so the coolant going to the IACV is as useless as the coolant going to the bottom of the TB (FITV) i bypassed the FITV, should i just bypass the IACV coolant lines also? just run a hose between the 2 ports on the thermostat, or block them off??

im running a JRSC and have the hondata IM gasket. anything to keep temps down is a plus for me!!
 

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so the coolant going to the IACV is as useless as the coolant going to the bottom of the TB (FITV) i bypassed the FITV, should i just bypass the IACV coolant lines also? just run a hose between the 2 ports on the thermostat, or block them off??

im running a JRSC and have the hondata IM gasket. anything to keep temps down is a plus for me!!
It's actually more useless, because the IACV does not depend on the coolant at all for its operation, and I can't help but wonder how being exposed to 200 degree water helps an electric motor last a long time... Disclaimer of course that you would have the possibility of one of those systems icing in extremely cold conditions where there's also high humidity, but when does that happen? Again, never heard of anyone having problems.

You definitely want to run a hose between the two ports. I just cut one of the hoses running to the IM so it fit across to the other port on the thermo housing, so coolant continues to flow in the same loop, you've just re-routed the loop so the FITV and IACV are no longer exposed to it. And again, you can remove that brass plate by unscrewing the three bolts under the IACV if you want. It doesn't make any difference, but I think it looks a little cleaner.
 

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My car is running like total ass right now. It runs awesome on the highway but, every time I get to a light The Idle surges , and some times it starts surging so fast that when I try to take of (5 speed) It starts bucking and jerking so bad and have to pull over to the side of the road.

If I turn the car off and back on, it will start and run fine until the next time I have to stop.
I have already taken off the FITV and taken it apart and cleaned it all out. screwed in the plunger all the way in and then 1/2 turn back..no change

I am going to take my IAC valve off and clean it out real good tomorrow.. I really hope this fixes my problem.
 

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Idle was a problem after H22A swap. Cleaning my old ones only half worked, so I got a new one from Rock Auto. Works fine now.
 

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Overheating now

I ended up removing the throttle body and cleaning inside that big silver thing then cleaning the IACV. The IACV didn't need cleaning much to my surprise, so I put everything back together & ended up going over to a friends house for a bonfire, food and drinks. Her house is roughly in between 10 -15 minutes away. Well when I got to her house I happened to look down and my temperature gauge was heading towards the point of no return. I quickly shut off my car. Can anyone tell me why? I do know that when I disconnected the hoses I heard and saw a lot of fluid drop on the garage floor. I figured I would need to top off my coolant. I never did though until that incident. Can someone with some no-how give me some advice?
 

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You want to bleed the air out of the cooling system. There's a nipple, on top of the thermostat housing.
There is a whole process to go through. Look it up, and do it. Just topping things up doesn't get the air out.
Go through the process, and you should be ok (this a general-not expert-opinion). I had to do it a couple of times.
 
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