etarui

let us know how your method holds up in a few days...

i just did this mod to my 06 a few days ago too

i even took the 2 shorter hose off the car, and re-route the longest hose there.........

i bought 4 valve caps to cap those valve off........

will take a picture when i have time!!!

Thanks, moda_way. I will probably do it someday.

Oh I see, thanks. I will probably do that someday.

Here is a diagram i drew................(don't blame on my bad drawing!!)


i try to make it as simple as possible.......basically, from input of coolant, thru the TB, and then to the output of coolant, it uses 3 hoses.......1, 2 and 3......

i was thinking of buying those hose connector like JTso and other member here, but i decided not to because we don't need it!

A - that's where the coolant comes out..........
B - that's where the coolant goes back in............

so all we need to do is just use a hose to connect A and B...........

DO THIS ONLY WHEN THE ENGIN HAD COOLED DOWN!!

~the only thing i bought is the 5/16 valve cap.~

1. first disconnect hose #1 that's attached to A (yes coolant will spill out.......so hurry and do step #2)
2. use a valve cap to cap off A...................
3. disconnect hose #3 that's attached to B, again, coolant will spill out, so use a valve cap to cap off B
4. disconnect all the hose........the only hose we will save is hose #2
5. now use hose #2 to connect A and B together

and done..........for me i used some fresh water to clean up any coolant that i had spilled inside the engin bay...........and of course dry it with a towel.......

Done Product:


i used 4 valve caps............

2 for this:

and the other 2:


~hope this help for all the 2006 TSX people~ (sorry for this long post btw......lol)

PWPTSX, nice try but you got it all wrong. Just follow what etarui did instead.

**I DREW THE PICTURE WRONG**
but the done product is also a correct way to do this TB bypass mod.

Same as etarui did, but for me i just connected point A to point B using a longer hose (rearrange hose #2), without passing thru the "U" metal tube.....which is by the way, not necessary.

No, PWPTSX, what you did is re-route coolant away from the air sensor (I believe... MAF sensor?), which is also a good thing to do, but not the TB bypass. You've bypassed the air line in stead of the throttle body.

To confirm (JTso...),

According to this picture, B1 is the throttle body's coolant intake nozzle, and A1 is the throttle body's coolant output nozzle. By re-routing existing hose on the 06, you can complete this mod without the need for additional parts.



In fact, wouldnt' the optimal setup be to route the hose from B2 straigt to the return, at my newly marked "C1" point? Thus bypassing the throttle body and the air sensor all in one step?

I'm sure there are several ways to complete this mod, as there is typically more than one way to skin a cat. I performed this mod the way I did, as I wanted to keep it simple. In my method, only two lines are disconnected, and swapped.

afici0nad0 - I have driven approx 100 miles so far and no issues. I will contine to update over the next few days.

pwptsx, what your bypass mod for the 06?

all 3 hoses are anitfreeze line, no air line involved.

what you mean?

This is very simple, I did it on my LS1 Camaro 3 years ago. I had no side effects. I'll do it on the TSX whenever I have spare time.

1. Yes, you have the coolant flow path correct (B1 = in, A1 = out).
2. Your C1 reference is incorrect. C1 is the "air inlet" that gets routed to the injector ports when the coolant is at a certain temp. It has nothing to do with the lines going to the throttle body.
3. The bypass can be done many ways. The key point is to keep it simple and disconnect as little as possible.

Ok... so I'm a lil freaked out since this is my first mod ever... I have a 04 and I finished doing the TB bypass and made sure there were no leaks. Started the engine and boom.... there's the CEL. I did fill the coolant in the reserve tank about 3/4 of an inch above the max line. Would that cause the CEL to come on? Other than that the car feels fine and nothing else seems to be going wrong. Any help would be appreciated.

You probably forgot to reconnect the IAT sensor on the intake tube.

Nope.... I got all of the connections in place... unless I'm missing something... I would take pix but I dont have a digicam.... sister stole it from me. Anyhow, all wires are connected and all tubes are accounted for and connected. I did remove the wire that goes to the TB so I could manuever around better and for got to attach that at first and started the engine. Of course my engine started acting weird so I checked all connections again and connected that wire.

Capped off nozzle on TB. The one under the TB is also similarly capped


I was only able to find a straight connector that was the right size. It was white so the lil white thing you see in the middle of the pic is the connector that is connecting the 2 coolant hoses.


Just a general shot of the intake near the TB


Another general shot of intake where (I'm assuming) the IAT is attached.

Ok this is the best I could do as far as pix. Had to use my phone.

That is enough to trigger the CEL until you reset it.

how would I reset it?

You can borrow a scan tool from Auto Zone to reset the code, or disconnect the battery for a few seconds to reset the ECU.

Thanx a bunch.. I found some threads on how to reset the CEL but they were all kinda unclear. Thanx for the clarification.

your pics don't show up for me

yeah... they arent working for me either but it's ok... JTso helped me figure it out

i'm going to be tackling this mod tomorrow ... is there any difference between using a T fitting (3 outlets) vs. elbow (2)?

You only need to connect 2 hoses. Why use a T fitting?

Still holding up. No problems!

i couldn't find the appropriately sized hose barb

yeah those connectors are hard to find. The Pep Boys near my house had em but they were hard to find in the store. Took me 15 min to actually find it.

^ finally found the item at ace hardware. btw, i never even checked if this mod is good for automatics. i don't see there being any difference, but lemmy check to be sure ...

i found my hose mender at lowes, home depot didn't carry the right size.

I went to a Napa Auto, Home Depot, and Autozone... none of them had it and to my astonishment acehardware had it for $0.80 or something...

Update.... so I guess this is working out for me. Just one concern though. I've been watching my rpms a lot more carefully than usual and I noticed that when starting from a cold engine the rpms are at 1.5k after a lil driving the rpms drop to normal range 700-800. Anyone know if this behavior is the norm?

^^ normal. Mine are always higher right after startup and drop to 700-800 after a slight warmup.

^^ i haven't noticed anything of the sort. i consistently idle around 750rpm

It's normal for the idle rpm to be higher during a cold start. The rpm then stays at the idle speed after warm-up.

The ECU program idles a cold engine (ECT <125F) at 1500RPM and keeps AFR a little on the rich side. When ECT begins to rise above 125F, RPMs drop incrementally before finally settling at ~750RPM. I've verified this using an OBD2 scantool. It is true for both stock and reflashed programs.

I can verify that it's also true for the Hondata NA and SC refashes.

just finished the tb mod ... it was fairly straight forward and simple, just took me forever to get the clamp off of the bottom coolant line! i used a brass hose barb from ace hardware. on another note, i found something quite peculiar (crack in rubber tubing) on my injen cai). i don't wanna hijack this thread so i'll post in another forum.

i just did it... it changed the sound of my vtec.. ( atleast im pretty sure it did.) sounds crazy good. and i spilled alot of that blue liquid but im still almost full since the car is new lol =]