ok, I recently removed my tb, uim and lim and cleaned everything, replaced my primary fuel rail and p/d, did the tb butterfly mod, installed pineapple 6-port sleeves, and replaced hoses/cleaned stuff...now I need a replacement hose that went from the engine to the throttle body. I went by discount auto part, pep boys, and autozone, and couldn't find any preformed 90 degree coolant hose for the size i needed (to fit under the uim, where it attaches to the engine).



Any ideas on what I could use? What did you guys use?

I ripped my stock hose getting it off. I was thinking of taking off the hose from my parts car, adding a male/male hose connector, and adding an extra length of striaght hose to the bac....you thoughts, please....this is the only thing keeping me from putting it all back together and seeing what difference was made

Mazda dealership? (Bend over)

I just don't want to wait for them to ship it. (they don't have it in stock)

you could cap it off for now and get it running and then put the hose in later?



mike

but one end is under the uim...I'd have to remove the uim again to put the hose on later, wouldn't I?

I'd just cap it. It will get plenty of heat through convection to deactivate the fast idle. You may have to adjust the fast idle a little though. No big deal.



s

if you have long needle nose pliers (my 2nd favorite tool) it doable with the intake on



mike

yah, thats the hose that will have you cursing. The cosmo is soo much nicer, its on the rail.

Didn't the tb mod eliminate the fast idle? Also, are you refering to the BAC when you say it'll get enough heat? Does the BAC really need coolant?

I went to ACE hardware and bought 2 hose connectors, threaded on one end and ribbed on the other, and a 90 degree elbow, everything brass...if this doesn't work, I'll go ahead and cap it, but I'd like to know what to do about the BAC...any takers?

I went to autozone, and they found one; but only after telling me 6 times that they didn't have anything like that it's a heater hose for a ford something. Just make them go look for prebent hose that's pretty close to the same diameter it may be a little bigger than stock but still seals up fine.



Also it has to be cut on both ends to make it fit perfect.

Didn't the tb mod eliminate the fast idle? Also, are you refering to the BAC when you say it'll get enough heat? Does the BAC really need coolant? [/quote]

bac doesn't need heat does it??? He was talking about the fast idle cam, it has thermowax that melts as the coolant heats up, turning off the fast idle cam. I mean the bac doesn't have anything like that, it just runs though a pipe on the outside of it... hmm.......

well i can think of 2 things. 1. the bac valve had coolant in it from the factory, if they could have saved the $1 worth of hose and clamps then they would have. they dont have the coolant in the bac on the later cars and it works better.....



mike

i'd keep the bacv, but eliminate the coolant. just plug the nipple on the rear of the engine and the water pump housing and be done with it. You can remove the small piece on the bacv which has the coolant flowing through it, it's just two screws holding it on.

I just took the line from the front and looped it to the rear so there'd be some coolant flow in those areas instead of none.

I tapped and plug the holes on the engine and the TB, after doing the TB mod, i just put my bac back on too https://www.nopistons.com/forums/pub...IR#>/happy.png

cool, thats the best way to go about it in my opinion.

cool...now, I might sound stupid here, but that's never stopped me before: are these caps something I can get at any auto parts store? How tight does it have to be (pressurized system, right?)?



The brass fittings were going to work with some old hose cut to fit, but I think the more that I eliminate, the easier things will be.

cool...now, I might sound stupid here, but that's never stopped me before: are these caps something I can get at any auto parts store? How tight does it have to be (pressurized system, right?)?



The brass fittings were going to work with some old hose cut to fit, but I think the more that I eliminate, the easier things will be. [/quote]

um it has to hold about 15-20psi, not a lot.



mike

After I do the TB mod to mine to my engine I'm garbaging that BACV.No need for it after that.Just makes it easier to work on and one less thing that could go wrong.Look at how many rotaries never had it?Theres a reason for that. https://www.nopistons.com/forums/pub...#>/biggrin.png

this is why I'm keeping mine

most fuel injected vehicles have a IAC (idle air control) motor, on the FC the BACV is the IAC equivalent. It's not a big deal, it doesnt need coolant, and it doesnt make things much messier. You'll probably wish you had it after you do it unless you don't mind your idle wandering around when the alternator places varying loads onthe motor (and possibly dying unless you set your idle high, which is annoying also)

yea my car was dying after i took it off, that was ghey.

I have an '89T2. I don't have it anymore. My car idles at 800rpm. It idles very smoothly. It doesn't stall, die, or do anyting odd when it is cold or up to temperature. I'm not sure what the fuss is all about. https://www.nopistons.com/forums/pub...R#>/unsure.png

huh? Well its not tha big of a deal anyhow.... its one little piece

You don't have the coolant hose or the BACV?



hell just hitting the brakes at idle will effect the idle because of the vacuum in the brake booster.



technically speaking... the idle will not be constant without any sort of idle air control, the load is not constant.

Soon as this dies out, its going to the faq section.

In my previous post prior to that one I mentioned that I just looped the coolant hose that goes into that stuff into the back of the engine where it was going into originally.



I took all of that junk off as I did the throttle body mod. I followed RETed's writeup on his website, fc3s-pro. When I was done it ran like crap. Everything seemed cool with all of the vacuum connections so I broke out the trusty multi-meter (never leave home without one if you drive a FC) and reset the TPS. After that is was very nice.

want to try an experiment?



sit car at idle, turn on headlights, blower motor, rear defroster, and if you have power windows try rolling them up/down, all at the same time... then to add to the fun abruptly press the brake pedal down. Without a BACV I would be shocked if the idle didnt fluctuate... assuming your idle is at a 'normal' rpm.





where does your car idle? If it's high you won't have as much of a problem, high enough and it won't matter at all.

I'll try that when I'm warming up my car once I get out of the office tonight. For the past week it's been getting cold in Seattle (relatively cold). Well, cold enough to have a frosted over car in the morning. I sure don't miss living in the MidWest. https://www.nopistons.com/forums/pub...DIR#>/wink.png I turn over the engine and it sparks to life like always. No stumbling at all when it's cold like that. I then turn on the heater to full blast and get the rear defroster (minus two lines in the middle https://www.nopistons.com/forums/pub...DIR ) going to defrost the windows. It doesn't seem to mind that at all. Like I said, I'll try that out. But so far my car did not inherit any of the problems like some other cars have once they took this stuff out. Beats me. It's not as though I did anything special.

do you still have the AWS solenoid?



you seem to be talking about during cold start, the test should be done when the engine is at operating temperature already.



also where is it idlin (at operating temperature)



depending on what all you have removed, there may still be components influencing the idle at cold start, you've probably removed the thermowax since this is about that coolant hose, but theres still the aws solenoid... is that gone too?



in any case, theres no secret here, it's needed to hold the (reasonably low) idle steady under the varying loads... Even those who switch to standalone ECU like the haltech e6k still retain the BACV and the e6k supports it right out of the box, why would they bother with supporting the PWM BACV if it wasnt a desireable feature? It really depends on what you plan on doing at idle and how high you want your idle.

i kept the bac after needing an annoying 1500rpm idle to put my top down. Keep it baldy

yah, you will want the bac if you put an electric fan on later



mike

I did the same as Jerk racer, took off the bac and ran the hose from the water pump to the rear of the engine, the hose fits pretty good. I ran like this for about 3 weeks and my idle was rough, but the car ran pretty much the same as before. However I still have my rats nest and and I didn't like the fact that the coolant hose was rubbing against the intake and fuel lines. So I just replaced all the hoses on the TB and put the BAC on again. I really like the look of the engine with the bac and hoses removed though, looks much cleaner.

If you plan on keeping your PS and AC keep the BAC. I have all of that **** removed on my AE, so I just ran a line from the nipple on the front to the one on the back. But on my vert I still have PS, but removed the BAC, and it will die when under a load at idle. All it does is compensate for load on the engine.

OK, OK. Tonight I tried that test after driving in traffic for twenty minutes. Warmed up engine (steady at about 87 Celcius), heater on full steam, brights on, rear defroster on, both windows in motion, and I was getting on and off the brakes. Idle started at 800rpm then would slowly go up to 1,000rpm then settle back down to 800rpm. The idle only moved this much when the brakes were used. Otherwise it's movement was barely any at all. It wasn't bad and it never acted as though it was going to die.



There is no BAC or AWS on my car anymore. I double checked just to make sure my memory wasn't wrong. It wasn't. Everything is gone from in there. It beats me why it runs so nice when the concensus says it should do otherwise.

so your idle is normally around 1000rpm?

He said its normally 800 but after hitting the brakes and stuff it went to 1000rpm.

my gsl-se does that too, i need the variable resistor to go leaner than stock....



mike