Throttle body coolant bypass?
Ben91RS
09-02-2006, 02:50 PM
I just recently bought a 91 Accord EX with the F22A4 engine for a daily driver. Right now I'm tearing it apart for a full tune-up and timing belt, and trying to make it roadworthy again.
Anyway, while I was cleaning the throttle body I noticed that there are coolant lines running to the throttle body. I know that a lot of cars now have these, and I know that is a common mod on the late-model GM motors (TPI, LT1, and LS1s in the Camaros, Firebirds, Corvettes, etc.) to bypass those coolant lines from the throttle body, supposedly keeping the incoming air just a little cooler. Should the same apply for these cars too, or is this just another one of those "free mods" that usually don't really do anything?
I know that it will probably make little to no difference in power, just curious if anyone with a Honda has tried it?
Anyway, while I was cleaning the throttle body I noticed that there are coolant lines running to the throttle body. I know that a lot of cars now have these, and I know that is a common mod on the late-model GM motors (TPI, LT1, and LS1s in the Camaros, Firebirds, Corvettes, etc.) to bypass those coolant lines from the throttle body, supposedly keeping the incoming air just a little cooler. Should the same apply for these cars too, or is this just another one of those "free mods" that usually don't really do anything?
I know that it will probably make little to no difference in power, just curious if anyone with a Honda has tried it?
jeffcoslacker
09-02-2006, 05:41 PM
I'm interested to see what the answer here is...throttle body bypass helps coldstart idle stability and allows it to come into emissions compliance quicker, but I'd think that the effect of eliminating it would be minimal, and probably not worth the effort, but like you, I'm curious.
How 'bout if you bypass it and hook lines to it run to a coil around a cold can with dry ice and you pump glycol through it...:grinyes:
...probably end up with a cracked throttle body and a big mess...:shakehead ...oh well, the price of discovery! To the Bat Cave!:lol:
How 'bout if you bypass it and hook lines to it run to a coil around a cold can with dry ice and you pump glycol through it...:grinyes:
...probably end up with a cracked throttle body and a big mess...:shakehead ...oh well, the price of discovery! To the Bat Cave!:lol:
jason-1995fbody
09-03-2006, 01:02 PM
did this mod on my firebird
when i had it and it did nothing that
was noticeable
with out it in cold wheather you could get frost build up on the TB
when i had it and it did nothing that
was noticeable
with out it in cold wheather you could get frost build up on the TB
Ben91RS
09-03-2006, 10:41 PM
Well, I may just try it and see what happens. It's not like it would be that hard to hook back up anyway.
Oh yeah, does anybody know if's it OK to turn the timing belt with the balance shaft belt off? It turns out what I thought was just a leaking water pump is actually a broken water pump. Part of the gear on the water pump has broken off and caused the balance shaft belt to slip off (it just fell out when I took the lower timing cover off, along with parts of the gear and some of the rollers in the bearing for the WP). Just need to know before I turn the engine over to see if it's in time before taking the timing belt off. I just hope and pray the timing belt didn't slip because of any of this, because this is an interference engine if I'm not mistaken.
Oh yeah, does anybody know if's it OK to turn the timing belt with the balance shaft belt off? It turns out what I thought was just a leaking water pump is actually a broken water pump. Part of the gear on the water pump has broken off and caused the balance shaft belt to slip off (it just fell out when I took the lower timing cover off, along with parts of the gear and some of the rollers in the bearing for the WP). Just need to know before I turn the engine over to see if it's in time before taking the timing belt off. I just hope and pray the timing belt didn't slip because of any of this, because this is an interference engine if I'm not mistaken.
Igovert500
09-08-2006, 02:28 PM
Keep in mind I have no experience with GM engines. But this is a topic I just ran across rather recently in a Mitsu forum. Some did it to clear up space, for convience in the engine bay, refering to teh same engines you did, as proof it will work fine. After doing this however, some had no problems, and some had issues with a much higher idling speed.
It's called the Fast Air Idle Valve, and basically it reads the coolant temp, and allows more air in, behind the butterfly in the TB, to bump up cold idle. So say normal idle is 700, some saw warm idles as high as 2,000. For others it worked fine. So my point is, make sure if you block this space off, make sure your blocking method is reversible...well that or I guess you could always just reset your base idle.
It's called the Fast Air Idle Valve, and basically it reads the coolant temp, and allows more air in, behind the butterfly in the TB, to bump up cold idle. So say normal idle is 700, some saw warm idles as high as 2,000. For others it worked fine. So my point is, make sure if you block this space off, make sure your blocking method is reversible...well that or I guess you could always just reset your base idle.
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