Honda Prelude Forum Honda Prelude Forum Header Right
» Site Navigation
» Home
»
» Related Sites
Google Links

» Wheel & Tire Center

» Log in
User Name:

Password:

Not a member yet?
Register Now!
Sponsors

Sponsors

Go Back   Honda Prelude Forum - Prelude Online.com > Honda Prelude Discussion > Honda Prelude FAQ > General FAQ
Register Home Forum Photo Gallery Active Topics Mark Forums Read

       


 
 
LinkBack Thread Tools Rate Thread Display Modes
Old 04-02-2003, 05:54 PM   #1 (permalink)
Offical Girl Hater.
 
dohcpower v2.0's Avatar
 
Join Date: Aug 2001
Location: Lexington KY
Posts: 5,164
iTrader: (2)
How To: TB & IAC Coolant bypass and block plate

Ok.. it is almost summer. No more cold weather. Time to do some free mods to help the car
stay cooler this summer. How about re-route the coolant lines to bypass the throttle
body, and IAC then make a block plate for the throttle body to eliminate irratic idle!

Tools:
10mm socket
12mm socket
flat tip screw driver
tin snips
drill w/ 15/64"s drill bit
needle nose plyers

Materials:
sheet metal
RTV hi temp silicone
3 small 10mm bolts

Time and Difficulty:
30-60 minutes / if you can remember and work a wrench, you're set!

Before you start:
Make sure the car is cool. Ther will be some coolant that leaks, and if the car is hot, you
could get burned. I'm adventerous, so i like to play with hot coolant!


Step 1
Remove the radiator cap to relieve pressure in the coolant system. Take off the coolant line
that is the farthest back, that is on top of the rear waterneck. Some coolant will spill from
this line, so be careful.


Coolant line removed


Step 2
Now remove the remaining coolant line that runs from the front port to the throttle body, from
under the throttle body. Now plug the end that was in the throttle body, into the rear port that
you removed the line from in step 1. Bascially, you are routing the coolant in a circle. You
can also remove the lines that are no longer in use from the IAC(on front side of intake manifold)
It is sometimes easier to remove the IAC to get the lines off unless you have a nice set of
angled plyers.



Coolant routed in circle


Step 3
Remove the intake from the throttle body. Remove the TPS harness(rear of throttle body), the
MAP sensor harness(on top of throttle body), and the vacume line.


Throttle Body almost ready to remove
__________________


XBOX Live - Doadus51
dohcpower v2.0 is offline  
Sponsored Links
Advertisement
 
Old 04-02-2003, 05:54 PM   #2 (permalink)
Offical Girl Hater.
 
dohcpower v2.0's Avatar
 
Join Date: Aug 2001
Location: Lexington KY
Posts: 5,164
iTrader: (2)
Step 4
Press the throttle rotor down. Pull the throttle cable out of the ridge of the rotor ,and let
the rotor go. You should be able to remove the pin, and place the cable aside. Make sure the
cable does not get bent. Remove the 2 12mm bolts, and the 2 12mm nuts. There is one wire harness
clip on the underside of the throttle body as well. I took tin snips, and cut it.


Throttle body out of car. Fast idle valve is on the underside


Step 5
Remove the 3 long 10mm bolts from the underside of the throttle body to remove the fast idle valve.
With the valve removed, there are 3 ports exposed. These are the ports you must block to prevent
erratic idle.


3 10mm bolts to remove


3 ports to be covered up


Step 6
Cut your piece of sheet metal to cover the surface of the bottom of the throttle body. Make sure
it is large enough to have all bolts go threw it. Place the fast idle valve on top of your
sheet metal. Use a nail, and a whackin device to mark the bolt holes. Drill the bolt holes, and
match up with the underside of the throttle body to make sure everything lines up properly.


Sheet metal cut to size


Marking Holes


Holes drilled


Making sure bolt holes line up with throttle body
__________________


XBOX Live - Doadus51
dohcpower v2.0 is offline  
Old 04-02-2003, 05:54 PM   #3 (permalink)
Offical Girl Hater.
 
dohcpower v2.0's Avatar
 
Join Date: Aug 2001
Location: Lexington KY
Posts: 5,164
iTrader: (2)
Step 7
Use the RTV silicone, and trace around the three holes. This will ensure a proper seal, which
should be pretty durn close to air tight. If there is a leak, you'll have a greater chance of
getting an erratic idle. That is NOT fun. Place the sheet on top of the sealent, and using your
smaller 3 10mm bolts, bolt down the plate. **You don't need to leave off the valve. if you can't
find 3 smaller bolts, or you want to have the car look factory, just place the metal between the
valve and throttle body!**



Sloppy, but does the job


Find 3 smaller 10mm bolts


Plate installed and ready to go back in car


Step 8
Place throttle body back in car, and re-install. This should be the opposite of removal. If you
can't figure out how to put it back in, then you shouldn't be doing this mod!


Fast Idle Valve Graveyard


Back in car w/o fast idle valve


Step 9
Let the sealent on the plate cure for 30-60 minutes. You don't want any of that junk getting into
the vacume system, or into your engine. Once it had dried, make sure everything is connected
properly, and start the car. Let it warm up, and listen for any erratic idle. The idle will
bounce badly if there is a problem. If there is a problem, you probably didn't seal the plate
well enough.

If there is no funny idle, then you are good to go! Be proud of your free mod. It will help
keep your car cool this summer, and maybe add a little power.

__________________


XBOX Live - Doadus51
dohcpower v2.0 is offline  
Old 04-02-2003, 06:14 PM   #4 (permalink)
veteran sharkdiver
 
Join Date: Mar 2002
Location: Sunnyvale, CA
Posts: 7,134
iTrader: (0)
There is nothing wrong with running this mod during the winter if the fast idle thermovalve is blocked. I've had this mod during sub 30 F weather with no idle issues at all.

Very nice writeup. Your block off plate looks like ass
__________________
sharkcohen is offline  
Old 04-02-2003, 06:14 PM   #5 (permalink)
Supporting Member
Unregistered
 
G_Loc's Avatar
 
Join Date: Sep 2001
Location: Miami, Fl
Posts: 2,970
iTrader: (0)
nice

its not really necessary to remove the TB though. I was cheap and in a hurry so I used a piece of cardboard from a nutrigrain box, lol.
G_Loc is offline  
Old 04-02-2003, 06:14 PM   #6 (permalink)
Supporting Member
Used to be a PreludeOwner
 
Join Date: Aug 2002
Location: Baton Rouge, LA
Posts: 335
iTrader: (0)
Nice!!!!!!

Since I will be doing the EGR block plate mod. I might as well do this at the same time.

Thanks.
__________________
Ken
kennethmina is offline  
Old 04-03-2003, 06:12 AM   #7 (permalink)
Marcucci Motorsports
 
Join Date: Mar 2001
Location: Dallas/Fort Worth, Texas
Posts: 9,097
iTrader: (11)
Ummm... not only is it easier to ditch the snips and go with gasket material, it's much easier. Cut a gasket the size of the valve and install it between the valve and TB. IT blocks off the passages and problem solved. Just make sure the valve and TB are dry (no coolant left). A cereal box works well if you can't find gasket material.

The sheet metal will get deformed with the snips, it might be tough to get it to seal even with RTV. I would suggest a "real" plate if you want to plate it off.
__________________


Proud Sponsor of - http://www.ntpog.org - http://www.s2000.org - http://www.preludeonline.com
1997 Honda Prelude is currently: Running | 1991 Isuzu Trooper is currently: Without AC
marcucci is online now  
Old 04-03-2003, 08:37 AM   #8 (permalink)
Putt Putt...Vroom Vroom!
 
Join Date: Dec 2001
Location: Balad, Iraq
Posts: 2,819
iTrader: (0)
my cereal box gasket has worked well for over a year now
__________________
Ben
DudewithaLude is offline  
Old 04-03-2003, 04:29 PM   #9 (permalink)
veteran sharkdiver
 
Join Date: Mar 2002
Location: Sunnyvale, CA
Posts: 7,134
iTrader: (0)
There is no reason not to just use cardboard between the fast idle valve assembly and the throttle body. All the "gasket" is blocking off is air flow, sicne the coolant no longer flows through it. I have a Kellog's Special K gasket.
__________________
sharkcohen is offline  
Old 04-03-2003, 05:04 PM   #10 (permalink)
Supporting Member
less whore than before
 
Join Date: Sep 2001
Location: Twin Cities
Posts: 3,657
iTrader: (0)
are you guys serious about the whole cereal box thing? it seems like your joking, but not really
khilgers is offline  
Old 04-03-2003, 05:05 PM   #11 (permalink)
Supporting Member
Unregistered
 
G_Loc's Avatar
 
Join Date: Sep 2001
Location: Miami, Fl
Posts: 2,970
iTrader: (0)
well his method makes it look cleaner since he completely took off the fast idle valve...

I may just use some 5mm aluminum I have lying around and do it this way to get rid of that crap.
G_Loc is offline  
Old 04-03-2003, 05:06 PM   #12 (permalink)
Supporting Member
less whore than before
 
Join Date: Sep 2001
Location: Twin Cities
Posts: 3,657
iTrader: (0)
Also, is it really necessary to do the TB block off. I mean I will still see some benefits from the coolant bypass right?
khilgers is offline  
Old 04-03-2003, 05:19 PM   #13 (permalink)
Offical Girl Hater.
 
dohcpower v2.0's Avatar
 
Join Date: Aug 2001
Location: Lexington KY
Posts: 5,164
iTrader: (2)
Quote:
Originally posted by G_Loc
well his method makes it look cleaner since he completely took off the fast idle valve...

I may just use some 5mm aluminum I have lying around and do it this way to get rid of that crap.
i've done 3 h22 throttle bodies, and did it on my g/f's 88 legend w/ the sheet metal, and i haven't had any problems yet. I just don't like the idea of having that valve down there, w/ open ports. Just looks better w/o it. Plus weight reduction!
__________________


XBOX Live - Doadus51
dohcpower v2.0 is offline  
Old 04-03-2003, 05:20 PM   #14 (permalink)
Offical Girl Hater.
 
dohcpower v2.0's Avatar
 
Join Date: Aug 2001
Location: Lexington KY
Posts: 5,164
iTrader: (2)
Quote:
Originally posted by khilgers
Also, is it really necessary to do the TB block off. I mean I will still see some benefits from the coolant bypass right?
You'll need to block the fast idle valve, or you will get a horrible erratic idle that will drive u nuts.
__________________


XBOX Live - Doadus51
dohcpower v2.0 is offline  
Old 04-03-2003, 05:28 PM   #15 (permalink)
Supporting Member
less whore than before
 
Join Date: Sep 2001
Location: Twin Cities
Posts: 3,657
iTrader: (0)
^^gotcha....we don't want that
khilgers is offline  
Old 04-03-2003, 05:47 PM   #16 (permalink)
Registered User
 
Join Date: Oct 2001
Location: Tempe, AZ
Posts: 3,287
iTrader: (0)
I think I've asked this before.....

Would anyone be interested in a "kit" made up of an EGR block plate, a plate to seal off the fast idle valve, and one for the bottom of the eacv on the front of the IM? I'm thinking just some lightly polished aluminum for pretty cheap. It will make it a lot more simple.
__________________
-Jeremy | Forbidden Motorsports

Yes....I'm back on PO!
4bidden is offline  
Old 04-03-2003, 05:50 PM   #17 (permalink)
Supporting Member
peace Jape
 
Join Date: Oct 2002
Location: Tulsa, Oklahoma
Posts: 403
iTrader: (0)
i oughtta do this before the track tomorrow
__________________
We need to understand that the more government spends, the more freedom is
lost. Instead of simply debating spending levels, we ought to be debating whether
the departments, agencies, and programs funded by the budget should exist at all.
RP 3/25/04
eu4ik is offline  
Old 04-03-2003, 05:54 PM   #18 (permalink)
veteran sharkdiver
 
Join Date: Mar 2002
Location: Sunnyvale, CA
Posts: 7,134
iTrader: (0)
Quote:
Originally posted by khilgers
are you guys serious about the whole cereal box thing? it seems like your joking, but not really
Quite serious. I'm not joking when I say that I have a Kellog's Special K gasket. I wouldn't kid around about that
__________________
sharkcohen is offline  
Old 04-03-2003, 09:51 PM   #19 (permalink)
Official *snow* Hater
 
Dotay's Avatar
 
Join Date: May 2002
Location: Indiana
Posts: 751
iTrader: (0)
Quote:
Originally posted by 4bidden
I think I've asked this before.....

Would anyone be interested in a "kit" made up of an EGR block plate, a plate to seal off the fast idle valve, and one for the bottom of the eacv on the front of the IM? I'm thinking just some lightly polished aluminum for pretty cheap. It will make it a lot more simple.
I'd be interested, how cheap? Under $20 and I think I would be down.
__________________


"I got it, I got it! I know your damned words, alright!?"
Dotay is offline  
Old 04-03-2003, 09:58 PM   #20 (permalink)
Supporting Member
less whore than before
 
Join Date: Sep 2001
Location: Twin Cities
Posts: 3,657
iTrader: (0)
^^I'm in too
khilgers is offline  
Old 04-03-2003, 10:23 PM   #21 (permalink)
Putt Putt...Vroom Vroom!
 
Join Date: Dec 2001
Location: Balad, Iraq
Posts: 2,819
iTrader: (0)
Quote:
Originally posted by sharkcohen

Quite serious. I'm not joking when I say that I have a Kellog's Special K gasket. I wouldn't kid around about that
my honey nut Cheerios gasket owns your special k gasket

btw, i am also quite serious, i really have a cheerios gasket


also, once someone shows you how to do it, i really doubt you'd need a kit to do the mods; its really rather simple to do.
__________________
Ben
DudewithaLude is offline  
Old 04-03-2003, 11:07 PM   #22 (permalink)
Supporting Member
PreludeOnline Premium Member
 
Join Date: Aug 2002
Location: SF Bay Area, Ca
Posts: 1,038
iTrader: (0)
Did you guys notice any difference with this mod?
__________________
Black 2001 5-spd
I/H/Hi-flowCat/E/P/VAFC/DC Short Shifter
Eibach Prokit/KYB AGX/Neuspeed front strut brace/Tanabe rear strut brace/Suspension Techniques rear sway
Energy Suspension Motor Mount Inserts
axio is offline  
Old 04-04-2003, 12:02 AM   #23 (permalink)
veteran sharkdiver
 
Join Date: Mar 2002
Location: Sunnyvale, CA
Posts: 7,134
iTrader: (0)
Quote:
Originally posted by axio
Did you guys notice any difference with this mod?
Well, I have a JRSC. I did this in conjunction with a hondata IM gasket install to help keep my intake temps down.
__________________
sharkcohen is offline  
Old 04-04-2003, 12:22 AM   #24 (permalink)
Putt Putt...Vroom Vroom!
 
Join Date: Dec 2001
Location: Balad, Iraq
Posts: 2,819
iTrader: (0)
I did this because I want my car to be like shark's (minus the SS ) j/k

I actually did feel a slight difference, when it was cold out it seemed to pull a bit harder, but I think that what gains this mod can get you can easily be mistaken for being in your head (ie, really not that much)
__________________
Ben
DudewithaLude is offline  
Old 04-04-2003, 05:42 AM   #25 (permalink)
Supporting Member
grrrrrrr
 
Join Date: Feb 2002
Location: Toronto
Posts: 1,506
iTrader: (0)