Coolant Bypass

[Dar-Dar]

After 3 months, the rubber caps started cracking. I switched them to the bypass. I'm going to look for silicone caps.

 

[CappyKD]

That stinks. I didn't cap mine, I looped my hose so the coolant still flowed. I only dust capped the ports on the throttle body.

 

[Dar-Dar]

That stinks. I didn't cap mine, I looped my hose so the coolant still flowed. I only dust capped the ports on the throttle body.

It does. I only like the capped method bc it looked cleaner.

 

[9000 RPM]

I would like to do this, but it would definitely have to be reversible due to cold winters.

In cold winters, the tb is as cold at start up with or without the bypass.

Honda did this for emissions purposes, that's all.

I had this bypassed on my FA5 in the dead of winter, 0 issues.

 

[Dar-Dar]

No issues on a 10 degree weather.

 

[Doublestack00]

Haven't done this to my 13 Si (yet) but I have been doing this to every Honda I have owned since the 90's.

 

[njhustler]

I'm doing it as soon as it starts to warm up again.

 

[13_PMM_Si]

Just read through this and found it all very interesting. I'm new to Hondas and have never heard of this before, but I live in Phoenix and will be installing an AEM CAI soon so it sounds like a worthwhile mod! Thanks everyone for posting this info.

 

[RobSBP]

This is excellent topic! Its nice to learn something new about car performance. I will do the throttle body coolant bypass soon.

 

[ericc191]

I will try to do this later today. My only question is.. the main thing of this mod is to take the hoses off the throttle body, and then connect the other sides of those together? If that makes sense.

Oh, and is it possible to do this without using any extra parts? Thanks

 

[RobSBP]

For R18, loop coolant hose back to the engine. Close both throttle body opening with shorter hose. No need for buy anything extra.

 

[sunofwolf]

I saw this thread about the throttle body bypass trick. The acurity CAI install includes it in there install ! This was done for emissions. Any thought's on this mod?

 

[webby]

I saw this thread about the throttle body bypass trick. The acurity CAI install includes it in there install ! This was done for emissions. Any thought's on this mod?

Has nothing to do with emissions.

https://9thcivic.com/forum/threads/coolant-bypass.6696/#post-141148

 

[sunofwolf]

the question I have is it only is needed below 32 degrees, It looks like I should hook it back up in winter which might not really be needed because I won't drive it in salted roads that's why I need a spare car like my Blue neon. The mechanic bypassed it all ready following acurity's instructions. This does has to do with too much hot air going into the engine Emissions still might be another reason as the ecu would give it a richer a/f at start up. there two reasons why honda did this. who knows what honda is thinking, but you might be right the main reason was for a froze TB>

 

[ron v]

If anyone does this. Get silicone caps. The plastic ones will crack within a year.