Coolant hose under throttle body, to engine, S4TII
 

Does this pain in the ass coolant line need to be there? Or can I cap it off at the engine?

Its part of the Thermowax accelerated warm up system, it goes through the TB. You could cap both ends, or loop a line between or just replace the stupid little bastards and leave everything intact.

^^^You could do that but expect to hold the throttle a little bit while the engine is cold. to the OP, just replace the line. Ive done it once and its easy, im about to replace it again because last time it was replaced the part was used. Go with OEM through mazdatrix.com or some place similar.

my rtek 1.7 kills the AWS, do i still need that coolant line?

you don't need that line if your not using the warm up. Id just cap it off.

sweet. that will make things easier. that hose is a bitch.

anyone else have a say?

AWS is not thermowax. The AWS removal function is for the 3K RPM startup. Thermowax keeps your idle speed at 1.5k and drops it to 750 RPM when warm. I'm not a fan of removing the thermowax personally. I kept mine during my engine build, and I'm out here in SoCal.

Good info. Thanks.

It's annoying not to have fast idle system, but you can live without it (although idle is especially bad if you eliminate the BAC valve as well). The fast idle system holds the throttle plate open (same as putting your foot on the gas) and then slowly closes it to a normal position once the engine warms up. Once you get used to installing the hose it's not too bad to deal with.

You do NOT want to remove the thermowax. Think about it like this...

How often do you need to remove your UIM (and the corresponding 90* hose) ?
Now how often would you like your car to idle?

Having your car die at every stop light is annoying, and the colder it gets the longer it takes before it will idle (if it does at all).

or you can get a S5 thermowax solenoid and the S5 90* hose. they are a TON easier to deal with.

if you live in IL, you really should keep it on there....
it looks like he has a t2, so wouldnt that be a questionmark shaped hose instead of the L hose?

^ Just the opposite. NAs have that question mark shaped hose that has to clear the UIM, while TIIs have the little 90* hose. S4 & S5 TIIs alike.

I removed my BAC valve and my thermowax on my Turbo II. I turned the throttle stop screw until the idle got to about 950 rpms warm, I live in NC and it's been pretty cold lately. My car will idle after about 30 seconds from a dead cold start. I have no problems with it dying on me as a result, but then again I don't have a stereo (yet), or A/C. My car is not a daily driver so I knew it wouldn't be a big deal to remove it, but now I would probably do it on a regular street car too. I felt like that coolant line was a biatch too and I was happy to cap that sucker!

I'll keep the hose. It's a 90 degree hose correct?

ya like one of the other posters said, how many times are you gonna be taking the UIM off?

I've had problems with that hose, it helps to just get a new piece of hose( much more flexible) and the screw type clamps, helped a lot for me at least.

Ahh, you're right. Although it does accelerate warm up as it idles at 1.5k when cold. :dunno:

I didn't say remove it...

You could cap both ends, or loop a line between or just replace the stupid little bastards and leave everything intact.

I removed mine, and yea, it doesn't idle when I first fire it up, but give it a few minutes and its fine.

^ Yeah, technically the thermowax does help warm the engine up :D, but that's not what the Rtek disables. That just nixes the air bypass solenoid (called AWS sometimes).

I was mainly replying to this:

I kept my thermowax, but I bypassed the BAC in the coolant loop. A hose directly from the water pump housing to the thermowax works.

I was cursing at that hose today pulling my UIM. But, I do like having the thermo wax intact for start up idle, thats for sure. Especially with all other emission removed. I just have some napa tubing on there and I think its too small which makes it worse. I really need the stock hose...

I found that the stock hose(or what ever was on there when I got the car) was too short and i went out and made a tube that was a little bit longer and that seemed to work much better.

i am going to use a longer hose, it was a bitch getting the hose clamp off when i removed my UIM, so i cut the hose.

that hose sucks a lot I am going to remove it when I put on my bigger turbo, the thermowax isnt a big deal on start up you just hold down the throttle for 45 secs instead of the car doing it it's self

i can just tell you that i don't have a bac, thermowax, and i capped off the hose and my car idles fine. I only have to hold the accelerator down for about 1 min when the engine is cold and then after that it idles fine.

My car used to idle after a min but after my BAC quit working, no such luck.

I think the thermowax is gone, so I've got another TB and BAC on the way.